这篇文章堪称机油选择和知识的圣典，在某些方面甚至完全颠覆了我们对机油的传统认识和理念。
机油选择，得此一文，足矣。在此郑重推荐！！！！！！！！！！
作者：Dr. Haas 译：零点（zlfati)
目录
Motor Oil 101....................................................2
Motor Oil 102....................................................6
Motor Oil 103..................................................10
Motor Oil 104..................................................14
Motor Oil 105..................................................19
Motor Oil 106..................................................24
Motor Oil 107..................................................30
Motor Oil 108..................................................36
Motor Oil 109..................................................42
Motor Oil 201..................................................47
Motor Oil Midterm Examination.........................57
Answers to the Oil Midterm Exam.....................59
Motor Oil Final Examination..............................61
Answers to the Oil Final Exam..........................68
[ 本帖最后由 狮行皓月 于 2014-5-27 00:22 编辑 ]

Motor Oil 101
Chapter One
第一章
I think it is time to go over passenger car automotive engine oils in detail. I will be writing several articles to be published soon so I will try to get some of it out here. I feel this is a very general topic for all car owners on this boards.
我想是时候该详细复习一下乘用车发动机润滑油了。很快我准备写几章出版，现在拿出一些内容放在这里。我感觉这些内容对于汽车拥有者来说是非常普遍的话题。
This is a very difficult topic to comprehend. Everybody including good mechanics think they are experts in this field but few understand engine oils. Most of what I hear is the opposite of the truth. It is howvever easy to see how people get mixed up as there is always some truth to the misconception.
这是一个很难真正理解的主题。包括一些优秀技工在内的甚至被认为是这个领域专家的人也少有真正懂得发动机润滑油的。我了解大多数人都有着错误的理解。这也是为什么经常能看到人们误解混淆了真相。
Please forgive me if I am too wordy or even verbose at times. I will be redundant for certain. This will be in areas that people have to hear things over and over again to get it right. Some will never be able to understand these concepts unfortunately. I base my thoughts on those whom I have been listening to in various automotive chat rooms and discussion with mechanics. I will try to minimize technical terms and be somewhat vague rather than exact. I will round and average numbers to make the point simple rather than mathematically exact. Thickness has the same meaning as viscosity. Viscosity is a measure of the resistance of a fluid (liquid or gas) to flow. Fluids with high viscosity, such as molasses, flow more slowly than those with low viscosity, such as water. Again, I am trying to explain general principals as I know them.
请原谅我有时太罗嗦。我可能会有过多的确认。只希望人们能一遍又一遍的听到正确的概念理解。不幸的一些人们永远无法理解这些概念。我把我的想法基于在各种汽车聊天室听说到的和与机械专家讨论得到的。我会尽量减少专业术语并以通俗大致的数据的而不是精确的。我将会用圆和平均数使要点简化而不是最求数学上的精确。厚度和粘度是同一个意思。粘度是一种用来测量流体（液体或气体）流动阻力的。高粘度流体像蜂蜜那样，流动速度比那些低粘度像水这样的慢。同样，我试图解释普通重要的我所了解的。
The greatest confusion is because of the way motor oils are labeled. It is an old system and is confusing to many people. I know the person is confused when they say that a 0W-30 oil is too thin for their engine because the old manual says to use 10W-30. This is wrong.
最大的困惑是因为机油被标记的方式。这是一个旧的体系而且使很多人感到困惑。我了 解到一些不懂的人说0W-30的机油对他们的发动机来说太薄（稀）了，因为旧的手册上说要是用 10W-30 的机油。其实这是错误的。
More confusion occurs because people think in terms of the oil thinning when it gets hot. They think this thinning with heat is the problem with motor oil. It would be more correct to think that oil thickens when it cools to room temperature and THIS is the problem. In fact this is the problem. It is said that 90 percent of engine wear occurs at startup. If we are interested in engine longevity then we should concentrate our attention at reducing engine wear at startup.
更多的迷惑发生因为人们认为机油再加热后会变薄（稀）。他们认为机油随着加热变薄 (稀）这对机油来说是个麻烦。其实真正的问题是机油冷却恢复到室温变会厚（稠）。据说，90% 的发动机磨损发生在启动瞬间。如果想要让发动机的寿命更长我们需要集中精力减少发动机在冷启动中的磨损。
Oils are chosen by the manufacturer to give the right thickness at the normal operating temperature of the engine. I will say this average oil temperature is 212 F，the boiling point of water. On the track that temperature is up to 302F. It is important to realize that these are two different operating environments and require different oils.
机油的选择要遵照手册规定发动机正常运行温度下的最适厚度（粘度）。发动机正常平均油温是 212F（100℃），也就是水的沸点。在赛道上油温会升至 302F（150℃）。 最重要的是需要知道这是两种不同的使用环境也需要不同种类的机油。
I will discuss driving around town first. Everything I say will be based on these conditions. At a later time I will discuss track conditions. Everything I say will be as accurate as possible without looking everything up and footnoting. I am trying to be general not ultra specific.
我们首先讨论在城市周围驾驶。我说的每句话将以这个为基础。稍后的时间我讲讨论赛道驾驶的情况。我说的尽可能准确不用查阅注释。我尽可能的用通俗易懂的方式而不是非常具体的。
One thing that is no longer important is the ambient temperature. Older automotive owner manuals often recommended one oil for the summer and another for the winter. This is still necessary for air cooled engines but is no longer a consideration in pressurized water cooled engines. These engine blocks are kept at around 212 F all year round. The oil is around the same temperature as well. This allows for a single grade oil all year round. Again, this is not the same as on the track where the coolant temperature is slightly higher and the oil temperature is much higher.
现在环境温度已经不再是关注要点了。过去的车主手册通常推荐夏季用一种机油冬季用 另外一种机油。这对于风冷发动机依然很必要但对于水冷发动机来说已经不在需要考虑这些了。因为这些发动机一年四季都保持着大约 212F（100℃）的温度。此外，这和赛道上的机油温度比冷却液温度高很多的情况是不一样的。
Please forget those numbers on the oil can. They really should be letters as AW-M，BW-N or CW-P. The fact that we are dealing with a system of numbers on the can makes people think that they represent the viscosity of the oil inside the can. The problem is that the viscosity of oil varies with its temperature. A “30” grade oil has a viscosity of 3 at 302 F ( 150 ℃ ) and thickens to 10 at 212 F ( 100 ℃ ). It further thickens to a viscosity of 100 at 104 F ( 40 ℃ ) and is too thick to measure at the freezing point of 32 F ( 0 ℃ ).
请忘掉机油上的这些数字。它们实际应该被书写成像 AW-M，BW-N 或 CW-P 这样。事实上我们处理的是一个数字系统使人们认为这个粘度就是机油再发动机里面的粘度。但问题是粘度随温度是变化的。30 粘度级的油在 302F（150℃）下粘度大约 3 左右， 而在 212F（100℃）时厚度（粘度）大约是 10 。当温度下降到 104F（40℃）时粘度为 100 左右，而温度下降到 32F（0℃）时机油厚重（粘稠）到几乎冻住了。
Oils are divided into grades (not weights) such as a 20，30 or 40 grade oils. This represents the viscosity range at operating temperature. But it is NOT the actual viscosity as we shall see. The issue is that viscosity is temperature dependent. Let's look at a 30 grade oil and how the viscosity of this grade of oil varies with temperature:
机油被划分成不同的粘度等级（而不是重量）例如 20，30 或 40 粘度。这些表示的是机油在发动机在正常工作温度下（100℃）的粘度范围。而不是我们看到的实际粘度。结果是粘度由温度决定。让我们看看 30 粘度级的润滑油粘度是怎样随温度变化的。
30 grade oil (often referred to as a 30 “weight” oil):
30 粘度级润滑油（也经常叫 30 重量级的油）：
Temperature（F）......Thickness
温度（华氏）...............厚度（粘度）
302...............................3
212...............................10
104...............................100
32.................................250（rough estimate）（粗略判断）
The automotive designers usually call for their engines to run at 212 F oil and water temperature with an oil thickness of 10. This is the viscosity of the oil, not the weight or grade as labeled on the oil can. I want to stay away from those numbers as they are confusing. We are talking about oil thickness, not oil can labeling. This will be discussed later. Forget the numbers on that oil can for now. We are only discussing the thickness of the oil that the engine requires during normal operating conditions.
汽车设计者通常需要他们的发动机运转在水温和油温大约 212F（100℃），机油厚度（粘度）在 10 左右的条件下。这是机油的粘度，而不是重量或标签上的级别。我要远离这些数字因为他们会把人搞糊涂的。我们讨论的关于机油的厚度（粘度）不是标签上的标识。这将在后面讨论。现在忘掉机油上的这些数字。我们仅讨论发动机在正常工况下需要的机油厚度（粘度）。
The engine is designed to run at 212 F at all external temperatures from Alaska to Florida. You can get in your car in Florida in September and drive zig-zag to Alaska arriving in November. The best thing for your engine would be that it was never turned off，you simply kept driving day and night. The oil thickness would be uniform, it would always be 10. In a perfect world the oil thickness would be 10 at all times and all temperatures.
发动机设计工作温度为 212F（100℃）无论外部温度是在阿拉斯加还是佛罗里达。你可以在佛罗里达九月驱车曲折前往十一月到达阿拉斯加。在这其中对发动机最好的做法就是不要熄火，日夜保持驾驶。这样机油的厚度（粘度）保持不变，总是 10 。最理想化是希望无论在什么温度下机油厚度（粘度）永远保持 10 。
If the thickness of oil was 10 when you got in your car in the morning and 10 while driving it would be perfect. You would not have to warm up your engine. You could just get in the car and step on the gas. There would be little wear and tear on you engine, almost none. Unfortunately the world is not perfect.
如果机油厚度（粘度）是 10 ，早上冷启动时是 10 开完还是 10 ，真能这样的话它可以说是完美的。你将用不着再去热车。你完全可以上车就踩油。而且几乎不会对发动机有任何磨损。不幸的是这个世界并不这样完美。
The night before when you drove home from work the car was up to the correct operating temperature and the oil was the correct thickness, 10. Over night the engine cooled to room temperature and the oil thickened. It is 75 F in the morning now (I do live in Florida). The oil thickness is now around 150. It is too thick to lubricate an engine designed to run with an oil having a thickness of 10.
晚上下班你驾车回家汽车发动机很快升至最佳工作温度，这时机油也达到了最适的厚度（粘度），10 。经过一晚的冷却发动机温度降至室温，机油也变厚（稠）了。早上气温 75F（24℃）（我住在佛罗里达）。这时机油的厚度（粘度）大约 150 。这样的粘度用来润滑设计润滑粘度是 10 的发动机太粘了。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:03 编辑 ]

Motor Oil 102
Chapter two. It gets more difficult.
第二章。变得更糟。
We left off discussing that a 0W-30 grade oil is not thinner than a 10W-30 oil. They both have the same thickness at operating temperature. The 0W-30 simply does not get as thick on cooling as the 10W-30. Both are still way to thick to lubricate an engine at startup.
我们停止讨论一个 0W-30 的机油不比 10W-30 的机油稀这个话题。在正常运行温度（100℃）下他们的厚度（粘度）是一样的。0W-30 的油仅仅是冷却下来后没有 10W-30 的厚（粘）。这两种油在冷启动时对于发动机润滑都是过厚（粘）的。
I have heard several people say that Porsche specifically prohibits a 0W-XX engine oil，that it is too thin. Now here is the partial truth I spoke of earlier. We will discuss multi-grade oils. Earlier we said that a straight 30 grade oil has a thickness of 10 at the normal operating temperature of your engine. The multi-grade oils 0W-30 and 10W-30 also have a thickness of 10 at 212 F.
我曾经听过有些人说保时捷明令禁止使用 0W-XX 的机油，因为那太薄（稀）了。现在我先说一下实际的情况。我们将讨论多级机油。之前我说过一个纯30粘度的机油在发动机正常运行温度（100℃）下厚度（粘度）大约为 10 。多级机油 0W-30 和 10W-30 在 212F（100℃）时厚度（粘度）其实也是 10 。
The difference is at 75 F，your startup temperature in the morning.
不同在于 75F（24℃），也就是你早上冷启动温度时。
Oil type...........Thickness at 75 F..........................Thickness at 212 F
机油类型........厚度（粘度）在75F（24℃）........厚度（粘度）在212F（100℃）
Straight 30……...........250...................................10
10W-30......................100....................................10
0W-30........................40 .....................................10
Straight 10.................30.......................................6
Now you can see that the difference between the desired thickness your engine requires ( = 10 ) is closest to the 0W-30 oil at startup. It is still too thick for normal operation. But it does not have far to go before it warms up and thins to the correct viscosity. Remember that most engine wear occurs at startup when the oil is too thick to lubricate properly. It cannot flow and therefore cannot lubricate. Most of the thick oil at startup actually goes through the bypass valve back to the engine oil sump and not into your engine oil ways. This is especially true when you really step on that gas pedal. You really need more lubrication and you actually get less.
现在你能发现冷启动时最接近发动机最佳粘度（=10）的机油是 0W-30。对于发动机正常运行温度下的粘度，它还是太厚（粘）了。但用不了预热多久它的粘度就会降至正常值。要记住大多数发动机磨损是发生启动时，那时机油太厚（粘稠）不能达到最佳润滑。它不流动因此不能润滑。大多数厚（粘稠）的机油在启动时实际上通过旁支泄压阀又流回到油底壳而不能进入发动机油道。这一点更为明显的发生在你踩下油门踏板时。你其实想获得更多的润滑但与实际正好相反。
Note that a straight 10 grade oil is also too thick for your engine at startup. It has a thickness of 30. Yet at operating temperatures it is too thin having a thickness of 6. It needs to be around 10. The oil companies have added viscosity index improvers or VII to oils to solve this dilemma. They take a mineral based oil and add VI improvers so that it does not thin as much when it gets hotter. Now instead of only having a thickness of 6 when hot it has a thickness of 10, just as we need.
请注意纯 10 粘度级的机油在你启动时都是过厚（粘）的。它的粘度大约为 30 。然而在正常运行温度下它又变的过于薄（稀），仅仅厚度（粘度）为 6 。这个数值需要在 10 左右才行。机油厂家不得不添加粘度指数改进剂（VII）来解决这个问题。他们将粘度指数改进剂加入到矿物基润滑油中使它在加热后不会变得那么薄（稀）。这样就会得到我们想要的，加热之后不是厚度（粘度）为 6 ，而是厚度（粘度）为 10 的油了。
The penalty is the startup thickness also goes up to 100. This is better than being up at 250 as a straight 30 grade oil though. Oil with a startup thickness of 100 that becomes the appropriate thickness of 10 when fully warmed up is called a 10W-30 grade motor oil. This is NOT as thick as a straight 30 grade oil at startup and it is NOT as thin as a straight 10 grade oil at full operating temperature.
带来的缺点是启动时厚度（粘度）又会上升至 100 了。但这比起纯 30 粘度级启动时 250 左右的厚度（粘度）要好得多。这种启动是厚度（粘度）在 100 左右，充分热车后粘度在 10 左右的油被叫做 10W-30 级别润滑油。这种油在启动时不会像纯 30 粘度级的油那样厚（粘稠），达到正常运转温度后也不会像纯 10 粘度级的油那样薄（稀）。
The downside of a mineral based multi-grade oil is that this VII additive wears out over time and you end up with the original straight 10 grade oil. It will go back to being too thin when hot. It will have a thickness of 6 instead of 10. This may be why Porsche (according to some people) does not want a 0W-30 but rather a 10W-30. If the VII wears out the 0W-30 will ultimately be thinner, a straight 0 grade oil. When the VII is used up in the 10W-30 oil it too is thinner. It goes back to a straight 10 grade oil. They are both still too thick at startup, both of them. The straight 0 grade oil，a 5 grade oil and a 10 grade oil are all too thick at startup.
对于矿物基多级润滑油缺点是当粘度指数改进剂消耗殆尽之后就会变成原始的纯 10 粘度级机油了。它又变回加热后过薄（稀）的油了。它的厚度（粘度）将不再是 10 而是 6 了。这可能就是为什么保时捷（一些人所说的）不让用 0W-30 而用 10W-30 的原因。如果粘度指数改进剂消耗殆尽 0W-30 的最终会变得更稀，像一个纯 0 粘度级的油一样。 当 10W-30 中的粘度指数改进剂消耗完之后也会变得过薄（稀）。它又变回了纯 10 粘度级的油了。他们在启动时都是过厚（粘）的。纯 0，5，10 粘度级的油在启动时都是过 厚（粘）的。
This is just theory however. With normal oil change intervals the VI improver will not wear out and so the problem does not really exist. In fact，oils do thin a little with use. This is partly from dilution with blow by gasoline and partly from VI improvers being used up. What is more interesting is that with further use motor oils actually thicken and this is much worse than the minimal thinning that may have occurred earlier.
然而这仅仅是理论。在换油周期内粘度指数改进剂不可能完全消耗，所以这个问题也不是真实存在的。事实上，机油使用后仅仅是变薄（稀）了一点。这一部分来自汽油的稀释另一部分来自粘度指数改进剂的消耗。更有趣的是随着使用机油会变厚（稠），这比 早期变薄（稀）那么一点点更为严重。
Synthetic oils are a whole different story. There is no VI improver added so there is nothing to wear out. The actual oil molecules never wear out. You could almost use the same oil forever. The problem is that there are other additives and they do get used up. I suppose if there was a good way to keep oil clean you could just add a can of additives every 6 months and just change the filter, never changing the oil.
合成油就完全不同了。它不添加粘度指数改进剂也就不存在消耗。事实上油分子是不会消耗的。你几乎可以永远使用下去。问题是其他的添加剂会消耗用尽。瞎想下，如果能有一种方法能保持机油清洁，你仅需每 6 个月加一回添加剂更换机油滤芯，永远不用更换机油。
When the additives wear out in a synthetic oil it still has the same viscosity. It will not thin as a mineral oil. The fear that some say Porsche has that oils thin when the VII runs out is not applicable to these synthetic oils. These oils will always have the correct thickness when hot and will still be too thick at startup as with all oils of all types，regardless of the API / SAE viscosity rating.
当合成机油中的添加剂消耗殆尽之后他仍然保持同样的粘度。他不会像矿物油那样变的很薄（稀）。人们担心一些说在保时捷上粘度指数改进剂消耗殆尽的情况在这些合成机油上并不存在。这些油在发动机正常温度的时候总是保持着正当的厚（粘）度，在启动时也会像所有油一样变的过于粘稠，无论 API/SAE 什么粘度级别都这样。
Automotive engine manufacturers know these principals of motor oils. They know there is thinning or thickening that will occur. They take these things into account when they write that owners manual. Mineral oil change recommendations will generally include shorter time intervals than those of synthetic oils.
汽车发动机制造厂家了解机油的这些重要特性。他们知道机油会有变厚（稠）变薄（稀) 的情况发生。他们把这些写入车主手册。矿物油相比合成油换油周期要短一些。
The reality is that motor oils do not need to be changed because they thin with use. It is the eventual thickening that limits the time you may keep oil in your engine. The limit is both time itself (with no motor use) and/or mileage use. The storage of motor oil in your garage, particularly mineral based oils, slowly ages the oil limiting its use later. Do not store huge volumes of oil in your garage that is exposed to extremes of temperature.
事实上更换机油并不是因为机油随着使用变薄（稀），而是由于最终变厚（粘稠）而影响了使用寿命的。这期限包括时间（即使不用）和使用里程。你把机油存放在车库，尤其是矿物油，随着存放时间的增长限制了它的使用。不要在车库里存放大量的润滑油而使他们暴露在极端的温度下。
End of part two.
弟二章结束。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:05 编辑 ]

Motor Oil 103
Part Three. You have a synthetic mind.
第三章。全合成观念。
Let us compare mineral and synthetic oils. I will not talk about chemical but rather functional differences. We discussed before how mineral oils are too thick at startup yet too thin when hot. The viscosity was corrected with the hot engine by adding VI improvers.
让我们来对比矿物油与合成油。我要说的不是化学而是功能上的差异。我们之前讨论过矿物油在启动时太粘稠而达到正常工况温度后又变的过稀。这通过添加粘度指数改进剂来改善。
A 10W-30 multi-grade mineral based oil is made from a 10 grade oil and has VI improvers added to thicken the product in a 212 F engine. It acts as a 30 grade oil when hot. It acts more as a 10 grade oil at startup. I remind you that a 10 or 5 or 2 grade oil is still too thick to provide lubrication at startup. They are all too thick at startup. There is currently no engine oil thin enough to operate correctly at startup. They all cause excessive wear at startup. Again, we are discussing the needs of my single hypothetical engine for around town driving.
10W30 的矿物基润滑油是用 10 粘度级的基础油通过加入粘度指数改进剂使它在 100 摄氏度的发动机中变的比之前粘稠，充当着 30 粘度级机油。在冷启动时它相当于 10 粘度级机油。提醒一下，所谓的 10 或者 5 甚至 2 粘度级机油在冷启动时对于提供润滑都是过于粘稠的。目前还没有足够稀的机油能在发动机冷启动时达到最佳粘度，它们在启动时都会导致发动机磨损。下面我们讨论一下单一假设城市驾驶环境发动机需求。
Oil type........... Thickness at 75 F .....Thickness at 212 F (For mineral based oils)
机油类型..........24摄氏度粘度............100摄氏度粘度（矿物油）
Straight 30..............250.....................10
10W-30..................100.....................10
0W-30.............. ......40......................10
Straight 10..............30.......................6
Straight 5................20.......................4
Straight 2................15.......................3
Straight 0................12.......................3 est.
Let's look at the make up of synthetic based oils. A 10W-30 synthetic oil is based on a 30 grade oil. This is unlike the counterpart mineral oil based on a 10 grade oil. There is no VI improver needed. The oil is already correct for the normal operating temperature of 212 F. It has a thickness of 10 while you drive to work. It will never thin yet has the same long term problem as the mineral based oil. They both thicken with extended age.
让我们看一下全合成机油的组成。一款 10W-30 全合成机油基于 30 粘度级基础油。它不像同样标号的矿物油基于 10 粘度级基础油。全合成机油不需要粘度指数改进剂，它在 100 度的正常发动机温度下有着适合的粘度 10 ，它将永远不会像矿物油那样在使用很长一段时间之后变的很稀。矿物油和全合成在超寿命后都会变稠。
Synthetic oils are derived in the laboratory. They are pure，usually nearly clear. I describe mineral based motor oils as a distilled，concentrated product. The impurities need to be removed from the raw petroleum. These oils are therefore less clean and contain many impurities. Again, the problem is really more of theory than practice but the difference does exist.
全合成机油起源于实验室。它们是纯的，通常接近纯净。我们说的矿物油是通过蒸馏提纯之后的成品，杂质要从原油中去除。因此，这些油相比之下不纯净包含许多杂质。其实，这个问题理论反面大于实际情况，但区别还是存在的。
People repeatedly say that synthetic oils are more stable in a hot engine. I hear that they lubricate better. The answer is yes and no. Oil molecules do not break down, just the additives. Generally, the synthetic oils do not have VI improvers so have less to lose.
人们总是说全合成机油在发动机中有更好的热稳定性。我听说它们润滑性更好。其实答案可以说对也可以说错。机油分子不会分解，仅仅是添加剂消耗。通常全合成机油不含粘度指数改进剂所以添加剂衰减情况轻。
There are some properties of synthetic oils that actually result is less wear than with mineral oils. These help increase your gas mileage as well. Due to a reduction of internal friction of the synthetic oil your engine will run a bit cooler. Wear increases as temperature increases, all other things being constant.
全合成机油的一些特性可以减少一些磨损。这有助于提高燃油经济性。由于全合成机油在发动机中减小内部摩擦使得发动机运转温度更低一些。其它条件不变的情况下，磨损增加会带来温度的升高。
A main advantage that the synthetic has over the mineral based oil is the ability to lubricate at startup. Both types of oil have the same specifications at 104 F， 212 F and 302 F. It is the startup viscosity characteristics that separate these oils. Synthetic oils do not thicken as much on cooling. They have better fluidity as the temperature drops.
全合成机油相比矿物油主要优势在于冷启动时的润滑。两种类型的油在 40 度，100 度 和 150 度都有着相同的规格。但冷启动粘度的不同可以区分他们，全合成机油不像矿物油那样粘稠，它在温度下降后有着更好的流动性。
A synthetic oil that is labeled as 10W-30 is less honey like as a mineral based 10W-30 motor oil at startup. They both have a thickness of 10 at normal operating temperatures. At 75 F the synthetic is not as thick. At 32 F the difference between the two is even greater. At 0 F the mineral oil is useless yet the synthetic works fairly well. Just keep the RPM to a minimum.
一个标着 10W-30 的全合成机油在冷启动时要比一个标着 10W-30 的矿物油流动性好。它们在正常发动机工作温度 100 度时有着相同的粘度 10 。在 24 度时全合成就不像矿物油那样粘稠。在 0 度时两种油区别更明显。在 -18 度时矿物油基本失效而全合成机油工作还很好，仅仅需要维持几分钟转数预热。
At temperatures below zero you will not be able to start your car with mineral oils while the synthetic oils may be used to -40 or -50 F. Oils are so thick that the normal method of viscosity measurement is not possible. Instead we measure if the oil can even be pumped or poured. Again, we are only discussing a single category of oil, the multi-grade 10W-30 API / SAE grade.
在温度低于 -18 度以下，用矿物油很难启动车辆，然而用全合成的话可以用在 -40 或 -46 度下。当机油粘稠到正常测量粘度方法无法测量时，取而代之，我们用机油泵可否泵送或机油可否被倾倒来测量。然而，我们只讨论了这一种多级机油 10W-30 API/SAE 等级。
I took an except from the web about Mobil 1 oils. They compared a 5W-30 synthetic Mobil 1 oil to a mineral based 10W-30 and a 10W-40 in ice cold conditions. The engine turned over at 152 RPM with the synthetic 5W-30 Mobil 1. The 10W-30 and 10W-40 mineral oils turned over at 45 and 32 RPM respectively. Neither of those engines started.
我在美孚一号官网外找到一份对比，其中有全合成美孚一号 5W-30 ，矿物基 10W-30 和矿物基 10W-40 。在冰冷条件下，全合成美孚一号 5W30 启动转数为 152RPM ，矿物油 10W-30 和 10W-40 分别为 45 和 32RPM 。引擎都没有发动着。
Motor oil becomes permanently thicker with exposure to northerly winter type weather. This is more of a problem to mineral based oils. Waxes form. This is why it is a bad idea to even store a bottle of oil in a cold garage. It goes bad on the garage self just because it is exposed to the cold.
对于北方冬季停在室外的车辆发动机油永远是过于粘稠的。这对矿物油更为严重，形成蜡状物。这就是为什么即使在寒冷的车库储存一瓶机油也是不对的，它会自己变坏，仅仅因为它暴露在寒冷中。
To recap, synthetic oils have similar characteristics as mineral oils at operating temperatures. The synthetic oil will however be less honey - like at startup even though it has the same API / SAE rating. Yet the synthetic 10W-30 grade oil is based on a heavier 30 grade oil while the mineral based 10W-30 oil is based on a thinner 10 grade oil. They are both similar at operating temperatures yet the 30 grade based synthetic is actually less thick at startup and much less honey - like at low temperatures. This is the opposite of what common sense dictates.
总的来说全合成机油与矿物油在发动机正常温度 100 度时有着相似的特性。同样 API/SAE 级别的全合成机油在冷启动时比像矿物油那样如蜂蜜那般粘稠的情况要轻。然而全合成 10W-30 是基于 100 度粘度更高的 30 粘度级基础油，矿物油 10W-30 是基于 100 度粘度更稀的 10 粘度级基础油。它们在发动机正常工况温度100度时粘度相当，而 30 粘度级全合成机油在低温冷启动时其实有着更低的粘度。这与大家通常的感觉正好是相反的。
This is worth repeating: The synthetic 10W-30 grade oil is based on a heavier 30 grade oil while the mineral based 10W-30 oil is based on a thinner 10 grade oil. They are both similar at operating temperatures yet the 30 grade based synthetic is actually less thick at startup and much less honey - like at low temperatures. This is the opposite of what common sense dictates.
这是值得反复来讲的：全合成 10W-30 是基于 100 度粘度更高的 30 粘度级基础油，而矿物油 10W-30 是基于 100 度粘度更稀的 10 粘度级基础油。它们在发动机正常工况温度 100 度时粘度相当，而 30 粘度级全合成机油在低温冷启动时其实有着更低的粘度。这与大家通常的感觉正好是相反的。
As one can see this is no easy topic. Are you with me?
正如所看到的，这是很难理解的话题，你跟上我了吗？
[ 本帖最后由 狮行皓月 于 2014-5-27 21:08 编辑 ]

Motor Oil 104
Part Four. It's not what we thought.
第四章。想象不到。
Now let us finish talking about the differences of mineral verses synthetic oils. I will compare the same weigh or grade of oils showing that the operating viscosities are the same whereas the startup viscosities vary:
现在我们不再讨论矿物油和全合成机油的的不同。我来对比相同粘度等级的机油（在发动机及工况温度 100 度时粘度相同的机油）在启动时粘度的变化：
Mineral oil:
矿物油：
Oil type...............Thickness at 75 F….......at 212 F….................at 302 F
机油型号............在24度时粘度................在100度时粘度..........在150度时粘度
Straight 30..........250...............................10.............................3
10W-30..............100...............................10.............................3
0W-30................There are none in this range
Synthetic oil:
全合成机油：
Oil type..............Thickness at 75 F........... at 212 F.....................at 302 F
机油型号............在24度时粘度….............在100度时粘度..........在150度时粘度
Straight 30..........100................................10.............................3
10W-30...............75.................................10.............................3
0W-30.................40............................ ....10.............................3
Since the synthetic oil thickens less on shutdown your startup will be so will the stress on your engine. This is perhaps the best thing the class has over the mineral based oils.
全合成机油从发动机熄火以后就会比矿物油随温度降低而变稠的趋势慢，所以冷启动发动机时就显得容易了，而且更利于建立油压。这也许就是全合成油好于矿物油最突出的地方了。
People sometimes use a thicker oil to minimize gasket leaks. This seems obvious to me. Repair the gasket. Do not destroy your engine with an oil that is too thick for proper function.
人们有时用比较粘的机油来减少烧发动机机油的情况。这在我看来显然是需要维修的。不要用太粘的机油来毁坏你的发动机正常的功能。
Some people have said they use thicker oils because they only use their cars every 2 , 3 or 4 weeks. They are afraid that thin oils will fall off the engine parts and result in a lack of lubrication at startup. Think about your lawn mower over the winter. I gets gummed up solid. The oil and fuel thicken over time resulting in engine failure. Anyway, oil on the surface of parts does not lubricate. It is the FLOW of oil between parts that lubricates. Thick，old，waxy oil can only be bad.
一些人说他们用粘稠的机油是因为他们每周仅仅用车两三次。他们害怕稀的机油在熄火后会流回油底壳而不在发动机零件表面导致再次启动时缺少润滑。想想你的草坪割草机进过一冬。我发现已经糟糕成固体了。机油和燃料随着时间变得粘稠最终导致发动机故障。总之，机油在零件表面不能润滑。只有在表面流动的机油才能起到润滑。粘稠的，旧的，蜡状的机油只能使情况更糟。
I have seen several car owner manuals that are now stating that oils do not need to be changed but every 7,500 miles or more. The same manual also states OR every 12 months, whichever occurs first. My feeling is that you can probably go 5,000 miles on the average (in a sports car) but you must change your oil in the spring time at a minimum，particularly up north. Oils form waxes in icy cold weather. There is a permanent thickening of the oil.
我看过一些车的车主手册说每 7500 英里左右或 12 个月保养一次（无论哪项先到）。 我认为平均一般跑 5000 英里，但在春季来临时北方的车一定要更换机油。机油在冰冷环境形成石蜡，使得机油永久的变稠。
Some automotive manufacturers are backing down on oil change intervals to 5,000 miles or less and some advocate changing the oil at least every 6 months as well. I think this is because of the tendency for oils to thicken in very hot engines (not ambient conditions, just hot engines). Also because of thickening from the cold of winter and from sludge build up that cannot be filtered out.
一些汽车制造商缩减换油周期为每 5000 英里或更少，而一些也主张至少每 6 个月换一次油。我认为这是因为机油在高温发动机里有变稠的趋势（不是周围环境，仅仅是高温发动机），也因为寒冷的冬季使油变稠和油泥的形成无法被过滤掉。
I truly believe that oil is much better being too thin than too thick. Over the years we have been going to thinner and thinner oils despite hotter engines with turbos and the like. The tendency is that people figure they need a 40 grade oils but then use a 50 instead. Better thinking is that if you think you need a 40, use a 30 grade oil instead. I firmly believe this based on all I know about oils.
我很相信机油变稀要比变稠好。多年来，我们用的机油越来越稀甚至像带有涡轮增压的高热发动机也是。人们的倾向是知道需要 40 粘度级的机油却用 50 粘度级的替代。更好的做法是如果你需要 40 粘度级的机油，用 30 粘度级的替代。我非常坚定的相信这是基于我所了解的所有关于润滑的知识得出的。
As it turns out synthetic oils do cling to parts better as they have higher film strength than mineral oils. Synthetics are thinner overall. They have greater slipperiness. Yet they stick better to engine parts. Again, this concept is the opposite of normal thinking.
事实证明全合成机油附着在零件表面相比矿物油有着更坚韧的油膜。全合成更稀，更滑，且对发动机零件附着更好。这个观念与一般人的想法正好相反。
The thickness of moving oil is measured in centiStokes or cS. Most engines want the oil viscosity to be around 10 cS at normal operating temperature. The really thick multi-grade oils have a viscosity of 20 cS at operating temperature. One is not twice as thick as the other, it is only 10 cS thicker.
机油的运动粘度用厘司（cS）来测量。大多数发动机正常工况温度下（100 度）希望机油粘度在 10 cS 左右。而实际上粘稠的多级机油在发动机工况温度下粘度达到 20 cS 。 一个没有两倍于另一个的粘度，它仅仅比 10 cS 粘。
As we increase the heat from 212 F to 302 F the most commonly recommended oil thins from 10 cS to 3 cS. The thicker oil drops from 20 cS to 4 cS. Note that in a very hot engine the difference between the two oils is now only 1-2 cS. In other words they have about the same thickness. There is little advantage to a thicker based oil as a 20W-50 at very high temperatures. No, the 4 cS oil is not twice as thick as the 2 or 3 cS oil. This difference is almost insignificant.
如果我们增加温度从 100 度到 150 度，大多数我们以前推荐的机油，粘度会从 l0cS 变到 3cS。而高粘度机油会从 20 cS 下降到 4 cS 。请注意，在非常热的发动机中两种油区别仅仅差 l-2 cS 。换言之，它们有着几乎相同的粘度。像20W-50这样的高粘度机油仅仅在非常高的温度下有微小的优势。其实 4 cS 机油并不比 2-3 cS 的机油粘稠 2 倍。 实际的差别几乎可以忽略不计。
There is a huge advantage of using the thinner, 10W-30 at startup where 90 percent of the engine wear occurs. At 75 F the thicker oil has a viscosity in the range of 250 cS while the thinner oil has a viscosity of 100 cS. The thicker stuff is 150 cS thicker. This is a very big difference. I am using the 20W-50 as my thicker oil example here.
90% 的发动机磨损发生在启动时，使用稀的 10W-30 机油有一个很大的优势。在 24 度时粘的机油粘度在 250 cS 左右，而稀的机油粘度在 100 cS 左右，相差 150 cS ，这是非常大的差距。这里我所说的粘的机油是以 20W-50 为例。
People are always asking about adding things as Slick 50 into the oil tank. Do not do this. The oil companies and engine manufacturers work together very hard to give you the product you need. Engines are running hotter, longer with more BHP from less CID. Smaller, more efficient engines are getting us more MPG and yet better acceleration. These engines last longer and are more reliable.
[ 本帖最后由 狮行皓月 于 2014-5-27 21:14 编辑 ]

有人总咨询关于添加如 Sick50（—种发动机机油添加剂）之类产品。其实用不着添加这些东西。机油厂家和发动机制造商紧密合作为提供你所需要的产品。现在的发动机运转温度越来越高，寿命更长，更小的排量更大的马力输出。更小更高效的发动机带给我们更高的燃油经济性和更好的加速度。这些发动机寿命更长，更可靠。
Part of that reason is the nature of the lubricants. There is a lot of competition to get us the best working motor oil. Independent additives cannot make the oil better and in many cases makes things worse. There have been engine failures as a result of adding some of these aftermarket additives to motor oil.
一部分原因是润滑油的性质。有很多竞争让我们获得最好的机油效果。单独的添加剂不能使机油更好反而很多情况变得更糟。有一些发动机损坏就是因为在机油中加入了市售的添加剂导致制的。
Motor oil that is labeled for RACING ONLY is not usable for every day driving. Often these have more additives that are toxic to your catalytic converters and the environment. These oils generally do not have detergents. These are very important for your engine unless you plan on taking it apart every few weeks and cleaning every single surface. The oils do not meet the API / SAE requirements for ratings as SJ，SL or now SM.
标着赛车油的发动机油对于普通日常驾驶是没效果的。通常这些油含有大量的添加剂，这些对触媒转换和环境是有毒的。这些机油通常不含有清净分散剂，而这东西对于发动机是非常重要的，除非你打算几周拆一次发动机来清洁每个零件表面。这类油一般没有 API/SAE 认证等级如 SJ ，SL 或现在的 SM 。
You do not need to use the exact oil type and brand that your car manual tells you to use. Oils are pretty general. They are not that different. Ferrari is married to Shell. If you call them up and ask to use Valvoline instead they will tell you that they have not tested that brand in their cars. They only tested the engine with Shell oils. They cannot comment on the performance of other oils in their engines. This is a fair statement. The reality is that the Shell and Valvoline oils of the same specification (viscosity, API and SAE ratings, synthetic or not) are very similar. ( I do have my bullet proof vest on ).
你不需要完全按照说明书推荐你的机油类型和品牌去使用。机油完全可以通用，它们没什么区别。法拉利与壳牌合作。如果你给他们打电话问用 Valvoline 品牌代替，他们会告诉你他们没做过这个品牌在他们车上的测试，他们只测试过壳牌机油，他们无法评论其他品牌机油在他们发动机里的表现。这是一个公平的陈述。其实相同规格的壳牌和 Valvoline 机油（粘度，API 和 SAE 等级，全合成或非全合成）是机器相似的。
People often say that their old 1980 car manual says to use a specific Brand-X motor oil. They keep trying to locate these older oils. First, just about any oil brand that meets the original specifications will do. Second，all oils are much， much better now. They are all much better. One could say that synthetic oils are better than mineral oils but it is hard to say that one brand is that much better than any other. Personally, I do stick to the big names. It does not mean that small motor oil companies are not as good. They could be better for all I know.
人们经常说他的 1980 年的老车手册明确说要用某某品牌的机油，他们努力寻找这些老机油。首先，无论什么品牌只要符合原来的规格就行了。第二，现在的油都比过去的要好很多。可以说全合成比矿物油好，但很难说一个品牌比另一个品牌的好很多、个人来说，我坚持用大品牌，但不表示小机油厂商的不好，它们可能比我所了解的更好。
Using an oil that is less thick at startup has other benefits. Let us compare a synthetic 10W-30 to a mineral based 10W-30. Both give you a viscosity of 10 cS at normal engine operating temperatures. They both thin to 3 cS at high temperatures. At 75 F tomorrow morning the story will be different. The startup viscosity of the synthetic will be 50 whereas the mineral based 10W-30 will be 100. Again, both are too thick at startup but the synthetic will cause less startup time period wear and tear. You will get a little better gas mileage too.
使用低粘度机油在启动时还有其他的好处。让我们对比—款全合成 10W-30 和一款矿物基 10W-30 。两种油在发动机正常工作温度下都有 10 cS 的粘度，在更高的温度下都有 3 cS 左右的粘度。而停车到第二天早上室外 24 度时就不同了，启动时全合成 50 cS 而矿物基 10W-30 将达到 100 cS 。虽然两种在启动时粘度都偏高，但使用全合成机油会有更短的启动磨损时间，也将会获得更好的燃油经济性。
The synthetic lubricated engine will turn over easier. This has the effect of using less power from your starter motor. It will last longer. Your battery has less of a current draw. This will also last longer. The battery was discharged less during the start so the alternator will rob less power from your engine to recharge. The alternator lasts longer and you get a little better gas economy. The only downsider of synthetic lubricants is the cost. They cost 2 or 3 times as much as mineral based oils. Never-the-less I use plain Pennzoil multi-grade mineral based 5W-20 in my Ford Expedition. This oil is thin enough at startup to have many of the attributes I just mentioned.
全合成机油在发动机里搅动更容易，这样可以使起动机马达负载更小增加寿命。你的电池也会消耗更少的电能，也会增加寿命。电池在启动时放电越少，发电机占用发动机用来充电的动力也就越少，这样发电机的寿命更长同时也将获得更好的燃油经济性。全合成唯一的缺点就是价格，它的价格是普通矿物油的 2 到 3 倍。尽管如此，我为我的福特远征用普通鹏斯多级矿物油 5W-20 。这油在启动时足够稀并且有我刚提到过的特征。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:16 编辑 ]

Motor Oil 105
Part Five. Let's use top gear:
第五章。最高档位：
Let's go racing. I will discuss driving in traffic jams in the Florida summer as well as racing in Sebring though there is no commonality. People lump these two driving situations together but there is no overlap.
让我们去跑比赛。我将讨论在佛罗里达的夏天拥堵的街道驾驶与在西布林跑比赛是否是一样的，尽管他们没有共性。人们却把这两种驾驶情况混为一谈，但其实这没有共性。
On the race track one usually uses all the BHP their engine can give them. You briefly step on the brakes for the corner then put the pedal to the metal the rest of the time. Your oil will get up to 302 F，but your cooling system is around 212 F. The engine produces tremendous heat but can only pass it off so fast to the cooling system. There is a lot of air moving past the cooling radiator so the antifreeze / coolant is able to get rid of the extra heat from this part of the system with relative ease.
在赛道上通常用尽发动机能输出的所有马力。仅仅在过弯刹车时短暂的休息，之后又会全油门输出。机油将升温至 150 度，但冷却系统依然在 100度 左右。发动机产生巨大的热量可以很快的通过散热系统传走。有大量的空气流过散热器使防冻液/冷冻剂能够相对容易的从这部分系统带走热量。
The temperature of oil on your gauge is not as hot as it really gets. This temperature is an average with oil from different parts of the motor. Some parts are hotter than others. It is said that some of the oil gets as hot as 400 or 500 F in these racing situations.
这个油温不是实际测量的那么热，而是机油流经不同零件的平均值。一些部分温度高于另一些，据说有些部分的机油在跑比赛的情况下能达到204到260度。
In an earlier section I said that thicker oils are usually needed in racing situations but not necessarily. Remember that a major function of oil is to cool the inside of your engine. In ASTM D 4485 3.1.4: “Terminology: Engine oil- a liquid that reduces friction and wear between moving parts within an engine, and also serves as a coolant." Since the oil with a viscosity of 10 cS at 212 F thins to a viscosity of 3 cS at 302 F we will get more flow. The pressure will go down some as well. This is OK as long as we have a minimum of pressure to move the oil.
在前面章节里我说过粘稠的油通常在比赛中需要，但不是必须的。请记住机油的一个主要功能是冷却发动机。在美国材料试验学会 ASTMD 4485 3.1.4 中：“术语：发动机油-一种在发动机内部运动组件之间能够减少摩擦和磨损并作为冷却剂的液体。”机油从 100 度时粘度为 10 cS 到 150 度粘度减到 3 cS ，我们会获得更高的流速，机油压力也会下降一些。这是我们所希望的用最小的压力让机油流动。
This increased flow will result in increased cooling by the oil. This is a good thing. You would probably want more oil flow in these situations and you get it. The hotter oil thins and this increases flow. The higher flow works harder to separate the engine parts that are under very high stress. It all works out for the better. Higher revving engines need thinner oils. You do not necessarily need to go to a thicker oil while racing. Only experimentation will tell.
增加流速就可以增加机油的散热能力，这是好事。在这种情况你会希望更多的机油流动，它做到了。热的机油粘度低增加了流速，更高的流速能够更好的分散发动机零件间巨大的压力，这些都使它工作的更好。高转发动机需要更稀的机油，你没必要在赛场上使用更粘的机油，只有实验会告诉我们。
The best way to figure out what viscosity of oil you need is to drive the car in the conditions you will use. Then use the oil viscosity that gives you 10 PSI per 1,000 RPM under those circumstances. For some reason very few people are able to get this simple principal correct. I cannot explain further.
想算出你用车环境下需要的机油粘度，最好的方法就是让发动机每 1000 RPM 获得 10 PSI 的机油压力。出于某种原因，很少有人能够得到这个简单又正确的方法。我无法进一步解释。
These same rules apply to engines of any age? loose or tight. Just because your engine is old does not mean it needs a thicker oil. It will need a thicker oil only if it is overly worn, whether new or old. Yet the same principals of 10 PSI per 1,000 RPM still apply. In all cases you need to try different grade oils and see what happens. Then choose the correct viscosity.
这个方法可以应用到任何年龄的发动机上。仅仅因为你的发动机老了并不意味着需要用更粘的机油。只有过度磨损时才需要更粘的机油，而不是新与旧。同样的原则每 1000 RPM 达到 10 PSI  压力依然可以应用在此。在所有情况下你需要尝试不同粘度级的既有并观察有什么不同，然后选择正确的粘度。
I used 0W-20 in my Ferrari 575 Maranello. It had over 5,000 miles on the clock. There will be a day (my estimate is 50,000 miles) when one will have to go to a 0W-30. In the future one will have to increase the viscosity to a 0W-40，then a 0W-50, maybe. You should use whatever it takes to get 75 PSI at 6,000 RPM during the lifetime of the engine. This formula works in all situations.
我在我的法拉利 575Maranello 中用过 0W-20 机油，并且用了 5000 英里。以后可能会有一天（我估计是 50000 英里）将会使用 0W-30 ，将来可能会增加到 0W-40 ，再之后会用 0W-50 。在发动机寿命里无论何时你需要保证它 6000 RPM 下要有 75 PSI 的机油压力。这个公式适用于任何情况。
Some people have tried this and occasionally get a somewhat low oil pressure while at idle. This is fine. There is no stress on parts at idle, the smallest oil flow will do the trick. It is at higher RPM where more BHP is produced. This is where we need the flow. Remember that Ferrari uses 75 PSI at 6,000 RPM as the place to test your oil viscosity needs. If your oil gives this value under your driving conditions then your lubrication system has been maximized. Period.
一些人尝试过这个方法在空闲时偶尔发现机油压力稍微低一些，这是没问题的，在空闲时零件间没有压力，少量的机油流过就可应对。这个参数是在高转和高马力输出时出现的，这时我们才需要流动。记住，法拉利在 6000 RPM 时需要 75 PSI 机油压力，以此来测试你需要的机油粘度。如果你的机油给出的值在你驾驶条件之下，表示你的润滑系统这期间已经满负荷了。
Do not go 5,000 miles with the same oil if you are racing your car. You should change the oil every 1 or 2,000 miles. If you drive your car around town then you need to change the oil for that situation. Use racing oil on the track and urban oil around town. The best situation as described by Ferrari is to use the 0W-40 around town and the 10W-60 "racing oil” on the track. It has to be that “hot” track though. A compromise situation would be to use the 5W-40 for both but this may not be optimal. Certainly, if you are just an urban driver as me use the 0W-40 or even a thinner oil as I do in my Maranello. Again, I used the 0W-20 grade.
如果你用你的车跑比赛不要 5000 英里不换油。你应该每 2000 英里左右更换一次。如果你在拥堵的城市驾驶，你也应该遵循这种情况。在赛道上用赛车油，在城市用普通油。以法拉利为例最好的情况是在城市用 0W-40 机油，在赛道上用 10W-6 0赛车油，必须是激烈高温的比赛。一个折衷情况可以用 5W-40 ，但不是最好的。可以确定的是，如果你像我一样是城市驾驶者的话，就用 0W-40 或更稀的，就像我在我的 Maranello 里用的一样。此外，我还用过 0W-20 的。
FYI. The Formula 1 cars that run at 15,000 RPM and higher use straight 5 and 10 grade oils.
你只需了解一下，一级方程式赛车在 15000 RPM 或更高转数时使用的是 5 或 10 粘度级机油。
Now let me discuss what people think is a similar situation to racing. That is hot summer traffic jam driving. Your car should be able to handle this. If you have problems then you have a problem with your car, most likely in need of a cooling system overhaul.
现在让我们讨论一下为什么人们认为炎热的夏天在拥堵的城市驾驶与跑比赛类似。你的车本应该能处理这些。如果你有疑问，为什么你的车在这时出现问题，最需要的就是检修一下冷却系统。
When you drive that car down the road mid-winter in upstate New York or mid-summer in Florida the engine and oil temperatures will be around 212 F. But your Florida vacation is suddenly altered by a hurricane. You have to get out of Tampa, but so do a million other people. It is now 95 F and you are in a snarl. Everyone thinks they need a thicker oil for this situation. This is false.
当你驾车在冬季的纽约北部或在盛夏的佛罗里达，发动机和机油温度将始终在 100 度 左右。但你的佛罗里达假期突然被飓风中断。你必须得到坦帕，但是这样做的还有无数其他的人。这时气温35度而且处于混乱之中。每个人都认为这种情况需要更粘稠的机油，这是错误的。
Your engine is not producing much heat at low RPM and low BHP output. The production of heat is relatively slow. It can easily be transmitted to your cooling system. The problem is that your cooling system has trouble getting rid of the heat. The oil and the coolant will slowly rise in temperature. They both rise together. The increase is no big deal for your oil. It goes to 220，then 230 F. The problem is that the cooling system can only handle heat up to 230 F. After that you overheat the cooling system and the car must be shut off. The oil never got that hot，It was just that the water got a little hotter than its system design.
你的发动机在低转低马力输出时不会产生过多热量，热量产生的相对较慢，可以很容易的传递给冷却系统。问题是你的冷却系统存在问题去排除这部分热量。机油和冷却系统会缓慢的升温。他们同时升温。机油的升温没什么大不了的，他上升到 104 度，一会 110 度。问题是冷却系统只能允许温度上升到 110 度。之后，冷却系统过热，你必须关闭发动机。这种情况下机油永远不会过热，仅仅是水温比设计值偏高。
You now see that overheating in traffic is a cooling system problem and not an oil system problem. Do not change to a thicker oil based on your traffic situation.
你现在知道了，在路上过热是冷却系统问题而不是机油润滑系统问题。不要基于交通环境而改用更粘的机油。
[ 本帖最后由 狮行皓月 于 2014-5-27 21:20 编辑 ]

Motor Oil 106
Part Six. A personal recommendation. (Updated in 2010)
第六章。个人忠告。（2010更新）
These are the motor oils I recommend. This is based on information that I just happened to collect. I have not gotten the specifications of all oils out there. My opinion on these oils is most based on viscosities. By this I mean less honey like at start up temperatures and appropriate for the required viscosity at operating temperature. I also looks at the oil tests others have done.
这是我对机油的忠告，基于我所了解的信息。在这里我没有得到所有的机油规格。我在机油上的观点大部分基于粘度。通过这些我希望机油启动时不像蜂蜜那样粘稠而达到发动机工况温度后又有着适合其所需要的粘度。我也在看别人做的机油试验。
I broke it down to several classes, 1-Fully Synthetic, 2-Race Track Oils for Street Use, 3-Semi-Synthetic, 4-Mineral (dinosaur) Oils. The asterisk (*) is my preferred from each group of very similar products. And these are usually easier to find in my experience. Remember, all oils are too thick at start up. There is no such thing as an oil that is too thin below 100 F. The thinnest motor oil made is still too thick at start up temperatures of 75 F.
我把它分成几个部分，1-全合成，2-街车用赛道油，3-半合成，4-矿物油。星号（*）是每组非常接近的产品中我更喜欢的，这些通常更容易买到。请记住，所有的机油在冷启动时都是过于粘稠的。没有机油在 38 度以下是过稀的。最稀的汽车机油在 24 度左右的冷启动时都是过于粘稠的。
It seems that many engines work best with a multi-grade 30 weight / grade oils. Others would do better with a 20 grade oil and few would require a 40 grade oil. You can only determine what is best by experimenting. Admittedly I did not think my Ferrari Maranello would need a 20 grade oil. In truth I could actually have used a 10 grade oil. A 0W-10 would be good but it simply does not exist for normal use. Red Line does make 2W? 5W and 10W oils (this acts as a 0W-10 multi-grade oil) but they are for racing only. One Formula 1 team has actually used these very oils off the shelf from Red Line.
似乎许多发动机工作最适合的是多级的 30 粘度级机油。其他的更适合于 20 粘度级机油，很少有需要 40 粘度级机油的。你只能通过试验确定哪个是最好的。不可否认，我不认为我的法拉利 Maranello 需要 20 粘度级机油。其实我想用 10 粘度级的，0W-10 的才好呢，但是这标号正常根本不存在。红线做过 2W，5W 和 10W 的机油（相当于 0W-10 多级机油）但它们只用于比赛。一级方程式车队实际上在用这些特殊的机油，而不在红线货架之上。
...Synthetic Class...
...全合成级...
60 Grade：     60 粘度级：
Agip Synthetic PC 20W-50 (a thick 50 wt oil)      （50 點度里偏粘的）
Redline straight 60 wt racing oil (racing only, acts as a SAE 20W-60 oil)*     （赛车油，相当于 20W-60 ）*
Penn Ultra Synthetic 10W-60
Shell Helix Ultra Racing Oil 10W-60
50 Grade：     50 粘度级：
Castrol Syntec 5W-50
Penn Platinum Synthetic 5W-50
Red Line 5W-50*
40 Grade：     40 粘度级：
Amsoil 0W-40 安索0w-40
Castrol European Formula 0W-30 (a thicker 30 grade oil，almost a 40 grade oil)* 嘉实多0w-30    （30 粘度级里偏粘的，接近 40 粘度级）*
Mobil One 0W-40 美孚1号0w-40
Penn Ultra Synthetic 5W-40
Renewable Lubricants Inc. 5W-40*
30 Grade：     30 粘度级：
Mobil One 0W-30 美孚1号0w-30
Penn (Any) Synthetic 5W-30
Red Line 5W-20 (a thick 20 grade oil)*  红线5w-20   （20 粘度级里偏粘的）*
Renewable Lubricants Inc. 0W-30*
20 Grade：     20 粘度级：
Mobil One 0W-20
Pennzoil Platinum Synthetic 0W-20
Renewable Lubricants Inc. 0W—20*
Valvoline SynPower 5W-20
...Race Oils for Street Use...
...街车用赛道油...
Use these when continued sump temperatures over 240 F are expected.
预期油底壳机油温度持续超过 116 度时使用。
60 Grade：     60 粘度级：
Redline straight 60 wt racing oil (racing only, not for the street，acts as a SAE 20W-60 oil)     （只用于比赛不能用于街道相当于20W－60机油）
Shell Helix Ultra Racing Oil 10W-60
Valvoline SynPower 20W-50
50 Grade：     50 粘度级：
Castrol Syntec 5W-50
Shell Helix Ultra 15W-50
40 Grade：     40 粘度级：
Red Line 5W-40 红线5w-40
Penn Ultra Synthetic 5W-40
Shell Helix Ultra 5W-40 灰壳5w-40
30 Grade：     30 粘度级：
Red Line 10W-30 红线 10w-30
20 Grade：     20 粘度级：
Amsoil 5W-20
Red Line 5W-20
...Synthetic Blends...
...半合成...
60 Grade：     60 粘度级：
Castrol Syntec Blend 20W-50
50 Grade：     50 粘度级：
Valvoline 20W-50
40 Grade：     40 粘度级：
Agip 4-Synt 10W-40 Valvoline Durablend 10W-40*
30 Grade：     30 粘度级：
Castrol Syntec Blend 5W-30 嘉实多5w-30
Motorcraft Blend 5W-30
Valvoline Durablend 5W-30*
20 Grade：     20 粘度级：
Motorcraft 5W-20*
Valvoline Durablend 5W-20
...Non-Synthetic...
...非合成油...
50 Grade：     50 粘度级：
None recommended - all relatively too thick at start up.     没有推荐-所有的启动粘度都太粘了。
40 Grade：     40 粘度级：
Penn regular Multi-grade 10W-40*
Valvoline All Climate 10W-40
30 Grade：     30 粘度级：
Penn regular Multi-grade 5W-30*
Valvoline All Climate 5W-30
20 Grade：     20 粘度级：
Penn regular Multi-grade 5W-20
Mobil Clean 5000 5W-20*
If while on the road you are forced to add oil there are rules. Let us say for example that our engine has synthetic Mobil One 0W-30. Use the same type and brand if you can. If you are using Mobil 1 then it is acceptable to mix different grades but use a close grade when possible. It is not a good idea to mix say 1/2 your oil tank with 0W-30 and 1/2 with 15W-50 Mobil 1. If there is no Mobil 1 available then use the mineral based Mobil oils next,.
当你在路上必须补机油时有这样一个规则。举个例子，发动机加的是全合成美孚一号 0W-30 机油，如果有条件最好添加相同类型和品牌的。如果你正在使用美孚一号也可以混入不同粘度级的，尽可能选个接近的粘度。最好不要在一半的 0W-30 发动机中混入一半容量的美孚一号 15W-50 。如果没有美孚一号可选也可以用美孚矿物油替代。
The last choice is to mix a synthetic of another brand. They should not react adversely if mixed but it may dilute additives. This is not a good combination. Use this combination if you must but only until an oil change can safely be performed some time soon.
最后的选择是混入其他品牌的全合成机油。它们虽说不能起反应但是会削弱机油添加剂效果，这不是一种好的混合，迫不得已才用这样，履行完职责就抓紧放掉，直到这时才能保证安全。
I personally used 0W-20 Mobil 1 in the 575 Maranello and for the first oil change I drained the Murcielago's (OEM) 5W-40 Agip and replaced it with 0W-30 Mobil 1. The engine became much quieter. A valve tappet noise disappeared. I then used the 5W-20 Red Line in the Lamborghini. Used oil analysis showed that this oil worked well for my non racetrack application. The same oil went into my Maybach 57. My Enzo Ferrari calls for the Shell Helix Ultra racing 10W-60 but I have used the Castrol Syntec European Formula 0W-30. This is different than the easy to find plain 0W-30 Syntec. It MUST say European Formula across the front of the label. I buy it at AutoZone stores but it is often mixed with the plain stuff. I am now using Renewable Lubricants Inc. (RLI) 0W-30 in the Enzo and 0W-20 RLI in the new Maybach 57s AMG.
我自己在法拉利 575 Maranello 中用过美孚一号 0W-20 并且首保放掉原车 OEM 的 Agip 5W-40 就换上了美孚一号 0W-30 ，发动机变得更安静了，气门挺杆声消失了。之后我又在兰博基尼上使用了红线 5W-20 ，旧油分析显示这个油在我不下赛道的使用环境上工作很好。同样的油也加入了我的迈巴赫 57 。我的法拉利恩佐说要加壳牌 Shell Helix Ultra racing 10W-60 ，但我却用 Castrol Syntec European Formula 0W-30 。这与和容易找到的普通的 0W-30 全合成不同。它一定说 European Formula 超越前面的标签。我在 AutoZone 商店买的它，但他经常混着普通的东西。现在我在恩佐里用 Renewable Lubricants Inc. (RLI)  0W-30 ，在新的迈巴赫 57s AMG 里用 0W-20 RLI。
You have to try by experimentation what operating oil grade your engine requires. In all cases however, you want the oil that gets least honey-like at startup and thins to the appropriate thickness for normal operation. Always recheck the oil label as they change a lot.
你必须通过实验尝试你的发动机需要什么粘度机油。无论在任何情况，你需要机油在启动时越稀越好不像蜂蜜那样并且在正常驾驶时有适当的粘度。需要经常检查机油的标签，它们变化很大。
[ 本帖最后由 狮行皓月 于 2014-5-27 22:56 编辑 ]

Motor Oil 107
Chapter Seven. What is the terminology from SAE and API.
第七章。术语。
Many think that the in 10W-30 means "winter".
许多人以为 10W-30 里的 "W" 是指的 "winter" 冬季。
From SAE J300 p.2:
来自 SAE J300 p.2：
"Two series of viscosity grades are defined in Table (1): (a) those containing the letter W and (b) those without. Single viscosity grade oils with the letter W are defined by maximum low temperature cranking and pumping viscosities and a minimum kinematic viscosity at 100℃. Single grade oils without the letter W are based on a set of minimum and maximum kinematic viscosities at 100℃ and a minimum high shear rate viscosity at 150℃. The shear rate will depend on the test method. Multi-grade grade oils are defined by both of these criteria....
两个系列的粘度等级被定义在表一：（a）这些包括字母 W 而（b）不包括（ aW-b 如 10W-30 ）。带有 W 单一粘度等级（如 10W-30 中的 10W ）被定义为最低的启动温度和泵送粘度，（如 10W-30 中的 30 ）被定义为 100 度时最低的运动粘度。不带 W 的粘度（如 10W-30 中的 30 ）基于 100 度运动粘度区间范围和 150 度高剪切率最低粘度区间范围。这个剪切率将取决于测试方法。多级机油通过这个两个标准定义。。。。。。
The W is just a designation of one type of testing vs another.
这个 W 仅仅表示一种相对于其他的测试类型。
What is the viscosity of the various grade oils? The definitions are as follows:
不同等级的机油粘度是多少？下面是定义：
From SAE J300, viscosities at 212 F...
来自SAEJ300，100度粘度...
20，range - 5.6 to 9.2     20 粘度级，范围从 5.6 cS 到 9.2 cS
30，9.3 - 12.4
40，12.5 - 16.2
50，16.3 - 21.8
60，21.9 - 26.1
By a modified analysis the min. viscosity at 302 F...     来自修正过的150度最低粘度分析...
20，2.6
30，2.9
40，2.9 - 3.7
50，3.7
60，3.7
Note again that the difference between the 20 grade and 60 grade oils at 302 F is only about 1 (one). Whereas the difference in viscosity at 104 F is 120 units. The 20 grade has a viscosity of 40 and the 60 grade a viscosity of 160. The difference at startup (75 F) is even higher，probably 250 or 300. At ice cold temperatures the difference is in the thousands.
再次注意，20 粘度级与 60 粘度级机油在 150 度时仅仅相差 l cS 左右，而在 40 度时相差 120 cS 左右，20 粘度级大约 40 cS 而 60 粘度级约为 160 cS。在冷启动 24 度时粘度差距会更大，能相差 250 到 300 cS 左右。在零下时相差要几千了。
The American Petroleum Institute，API，and Society of Automotive Engineers， SAE, have rated engine oil performance over the years. We have seen the ratings go from SA，SB，SC，SD，SE，SF，SG，SH，SJ，SL with SM to follow. SI and SK were eliminated as they are used by other businesses. There are over 3 dozen tests that oil now must pass in order to make the next higher rating. The tests are defined by the American Society for Testing and Materials, ASTM. Some tests have progressed to a zero tolerance level. For example there can be no sticking of any piston rings any more. I will compare the SL rated oil to the previous SJ oil in a few categories. For simplicity I will skip the units of measurement:
美国石油协会（API）和汽车工程师学会（SAE）多年来对机油实行等级划分。我们看到等级从 SA，SB，SC，SD，SE，SF，SG，SH，SJ，SL 到 SM 。SI 和 SK 被去除用在其他行业。想上升一个等级必须要进行超过 36 种测试并通过。这些测试由美国材料试验学会（ASTM）来做。一些测试要进行到零公差级别，例如活塞环不能有一点毛刺。我将小范围内对比从 SL 级别到早先的 SJ 级别机油。为了简单我将省略测量单位：
.......S J.......S L.......
.......30.......20.......maximum cam plus lifter wear     最大凸轮挺杆磨损
.......9.........7.8......sludge build up                          油泥形成
.......5.........8.9......varnish rating (more is better)     光亮级别（越大越好）
.......60.......45.......high temperature deposits           高温沉积物
.......17.......10.......high temperature volatility           高温挥发性
Other categories include: Resistance to rust，resistance to foaming, resistance to oil consumption, homogeneity and miscibility，flow reduction with varying amounts of absorbed moisture, gelation index and others.
其他类别包括：抗锈，抗起泡，抗消耗，同类混合性，吸湿性，冻结指数和其它。
As one can see just going from the previous SJ to the SL rating is a significant improvement. I cannot wait to get the upcoming SM oil into my cars. This is the current rating as of April 2010.
人们可以看出，从先前的 SJ 到 SL 级有着重大的进步。我迫不及待想给我的车用即将来临的 SM 级机油。这个级别从 2010 年 4 月开始流通。
Regarding cool whether gel formation, a small except from SAE j300 1999:
关于低温是否寒冷凝固，在 SAE j300 1999 之外一小部分
4. Because engine pumping，cranking and starting are all important at low temperatures the selection of an oil for winter operation should consider both the viscosity required for oil flow as well as cranking and starting, at the lowest expected ambient temperature.
4.由于发动机油的泵送与曲轴转数在低温启动时都非常重要，所以选择一款冬季机油需要同时考虑在最低气温时能否达到启动所必需的机油最低粘度。
Pumping viscosity is a measure of an oils ability to flow...during the initial stages of operation. Test in ASTM D 4684.....samples are tested after a slow cool cycle. This cycle has predicted as failures several SAE 10W-30 and 10W-40 oils which are known to have suffered pumping failures in the field after short-term (2 days or less) cooling. These field failures are believed to be the result of the oil forming gel structures that result in excessive yield stress and viscosity of the engine oil...
泵送粘度用来衡量机油的流动能力…在初始运转阶段。测试在 ASTMD 4684。…样本 经过一个缓慢的冷却周期后被测试。这个周期预测，作为一些已知在短期（2 天以内）范围冷却遭到泵送失败的 10W-30 和 10W-40 。这个失败范围是由于机油粘度过高导致产生过多的阻力…
A.2.1 …After preliminary warming, the sample is subjected to a controlled temperature/time cycle over 5 1/2 to 7 days. The cycle reproduces ...instability or reversion which has occurred during storage of oils in moderately cold cyclic conditions. Recent work shows relevance to engine oil pumpability failure. Oils exhibiting pour reversion have solids resulting from wax gel formation, at temperatures significantly higher than their ASTM D 97 pour points.
A.2.1…经过慢慢变暖，样品受到控制温度/时间周期超过 5 天半到 7 天 。这个周期复制…发生在适当的寒冷周期条件储存不稳定或逆转。近来工作显示与机油泵送失败由相关的倾倒流动性变化导致，凝固是由于石蜡遇冷形成胶状，这比 ASTMD97 中的倾点更值得关注。
Extracted，from ASTM D 4485-03 Standard Specification for Performance of Engine Oils，copyright ASTM International, 100 Barr Harbor Drive，Wets Conshohocken, PA 19428，USA.
摘录至 ASTM D 4485-03 发动机油执行标准详述，copyright ASTM International 100 Barr Harbor Drive, Wets Conshohocken, PA 19428, USA.
My point is that tests are not just laboratory concoctions. They design tests to match real life conditions.
[ 本帖最后由 狮行皓月 于 2014-5-27 21:24 编辑 ]

我的观点是，测试并不仅仅是实验室调和，他们设计测试与实际情况相匹配。
I used 5W-20 Pennzoil mineral based multi-grade oil in my Expedition as it has many of the low temperature characteristics of higher grade synthetic oils. My '04 manual states that the SUV is delivered with a Ford semi-synthetic oil and although regular oil can be used they recommend a semi or full synthetic oil. For the differential gear oil they used 75W-140 in my ‘98 Expedition but now recommend 75W-90. If I was towing 8,000 lbs. then I would need the semi or full synthetic 5W-20. But for my usual around town driving a plain, mineral based oil is plenty good.
我在我的远征（Expedition）中使用鹏斯 5W-20 矿物油因为它拥有很多全合成机油低温的特性。我的 04 手册规定这个 SUV 使用福特半合成机油，尽管常规机油也没问题但他们还是推荐半合成或全合成机油。不同的是我的 98 远征变速箱齿轮油要求用 75W-140 ,但现在建议用 75W-90 。如果我拖 8000 磅的东西，我会用半合成或全合成 5W-20 ，但对于我正常城市平常驾驶，矿物油也是很不错的选择。
Please note that it makes no difference what oil you are using. The 0W-20 Mobil 1 that is SL rated meets the same criteria as that SL rated 10W-30 synthetic or mineral based Pennzoil. That SJ or in particular that SH oil some people are looking for (from their older automotive owners manual) is no where near as good as any SL oil of today. Always use the most currently available, highest rated motor oil，even in the oldest，most worn engine. You may require a thicker grade but just make sure it is SL or SM rated.
请记住，用哪种机油都没什么区别。0W-20 的美孚一号 SL 与鹏斯 10W-30 矿物或全合成有着相同的等级标准。一些人在寻找 SJ 或尤其 SH  (他们的旧的车主手册上要求），这与现今的 SL 相比一无是处。即使是最老磨损很严重的发动机，经常用最新标准最高等级的机油是完全可以的。你可以选择更稀的粘度等级，但确保是 SL 或 SM 级别就行。
The SH rating was used in oils starting 1993. The SJ rating started in 1997 while the SL became effective in 2001 oils. According to ASTM D 4485，SL rated oils are superior to previous oils and from:
X2.3.1 and 2- SL oil is for use in current and all earlier passenger cars, sport utility vehicles，vans? and light trucks. This SL rated oil can be used in engines requiring SJ and All Earlier Categories.
SH 标准从 1993 年开始使用。SJ 标准从 1997 年，而 SL 从 2001 年生效。根据 ASTM D 4485 ，SL 级别机油优越于之前的标准，来自：
X2.3.1 和 2: SL 机油适用于现在的以及所有早先的乘用车，SUV ，箱货和轻卡。SL  级别机油可以用在需要 SJ 以及所有早先的级别种类范畴。
Concern： People are worried about the SM oils not having as much ZDDP as the SL and older oils. The reason ZDDP has been used for years is not because of its superior performance but rather its low cost and dual function as an antioxidant. It also has anticorrosive properties.
涉及到：人们担心 SM 级别机油相比 SL 以及更老的机油，ZDDP 会有所减少。ZDDP 被使用这么多年不是因为它优异的性能，而是它成本低廉又能充当抗氧化剂这双层功能。它还有防腐特性。
There are other additives. Some newer oils do not have any ZDDP, and they are excellent products. Just the same, I prefer oils with ZDP for now. The research shows that 0.03 is all that is needed and has the same function as higher levels. The only reason to have more is because your engine is consuming the ZDDP secondary to borderline lubrication from oil alone.
还有其它的添加剂。一些新的机油不含一点 ZDDP ，并且这些都是优秀的产品。其实都 一样，我更喜欢现在添加 ZDP 的机油。研究表明，0.03 就能达到要求，并且具有更高的水平。主要原因是发动机会消耗 ZDDP ，其次边界润滑只有基础油参与。
And lastly，too much can be corrosive itself and has shown in some tests to actually increase wear.
最后，很多本身具有腐蚀性，并在一些测试显示实际会增加磨损。
See: American Society for Testing and Materials- *****
参照：美国材料试验协会
........Society of Automotive Engineers- *****
........美国汽车工程师协会
........American Petroleum Institute- www,api.org
........美国石油协会