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Difference Between Motor Oil and Transmission Fluid
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Difference Between Motor Oil and Transmission Fluid
I work at an auto parts store and customers ask the difference between motor oil and transmission fluid. What would your explanation be? Quick and simple - to the point.
-- Tim McIlhenny, Bremerton, WA
Motor oil is for your vehicle's engine.  Transmission fluid is used by your steering system to keep its parts moving smoothly.  A couple of differences are the following:  1) an engine is designed to deal with the products of combustion, whereas an automatic transmission fluid (ATF) does not see contaminants from fuel burning.  An ATF is basically a closed system and the lubricant must last for a long period of time.  An engine oil must be drained to remove contaminants after a relatively short time/or mileage compared to an ATF.  Similar additive component types are used, but at different levels and different chemistries.  In an ATF, clutch friction is a very important consideration.
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