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得知合成机油也不是像有些厂商说的那样可以拉长机油更换的时间或者里程。而且在更换机油的时候最好要连同机油滤芯器一起更换。

下面我只是摘选了一部分，给大家大概翻译了一下，有兴趣的可以看看这篇***的前半段，将机油的区别。

To offset the higher cost of synthetic oil, some of the oil companies claim you can run the oil longer between changes. They say you do not have

 to change the oil every 3,000 miles. Valvoline does not make that claim. McClanahan says, "The additives in synthetics are superior but they still break down at the same rate and you need to replenish them often. We are unaware of any additive package that lasts longer than what the manufacturer recommends. Those 10,000-mile claims are ludicrous."

对于合成机油的高昂的费用，一些机油生产商声称合成机油允许发动机运行更多的里程而不用每 3000英里（5000公里）就要更换机油。valvolin胜牌（美国一润滑油厂商）没有做过这样的声明，McClanahan（胜牌公司的可能是科学家）说合成机油里的添加剂是比较好，但是它们也可能和矿物油分解的速度差不多，所以也需要及时的补充。我们现在还不知道有那种添加剂可以想有些生产厂家说的那样可以增长换机油的里程，而且这10，0000英里换一次机油有些荒谬。

The base oil is good forever. The additives and VI improvers break down over time. The thing that destroys the ability of the oil to lubricate is the accumulation of gasoline, dirt, and engine contaminates in the oil. Oil is supposed to get dirty. Its job is to remove contaminants out of the engine. Even with the superior additive package of the synthetic, contaminates still accumulate and need to be flushed out of the engine. Therefore, you need to change your oil often.

合成机油的基本油料可能是永不变质，但是添加剂和VI（viscosity index粘稠度）会随着时间而分解。造成机油润滑程度下降的原因有积碳，尘土还有引擎摩擦的残留物等等。机油的作用之一就是清理引擎的污染物，所以它肯定会变得越来越脏，就算是使用了优质添加剂的机油也会由于杂质污染物的累积需要经常更换。

Every time you change the oil, you must change the oil filter. The oil filter traps the dirt. By adding new clean oil and not changing the filter, all you are doing is adding dirt to the clean oil. An oil filter has a relief valve that allows oil to pass through the filter when it is full. A that point, you are circulating dirty oil.

每一次更换机油的时候，必须要换机油滤芯器，因为滤芯器用来隔离那些杂质的，如果只换机油而不换滤芯器的话，就相当于把杂质放进干净的机油一样，因为机油滤芯器的安全阀使机可以放出积满的机油，而此刻那些含有杂质的机油就会被滤芯器截留下来，所以不换滤芯器的话，里面存留的脏油就会和污染新加入的干净的机油。

以后看到好的***会继续给大家贴出来，共同学习。。。。