Questions and Answers

Transmission Fluid Versus Motor Oil

Q. I know this may sound stupid but here goes. My 2 cousins got into a big argument One said that you could run your car on transmission fluid instead of using motor oil, the other argued that you could not. They called me and asked for an answer. I told them that you could not. They wanted to know why not. I told them I didn't know for sure but I thought that parts in the engine would not be lubricated because of the thin nature of transmission fluid, and that the engine would probably freeze up. We are all women and haven't got a clue, please clarify if you would. (None of us are blondes.)

Thank You,
Pat

A. I never did equate hair color with intelligence. In fact, I have a friend who is a blonde and as long as I blow in her ear once a week to refill her head, she's as smart as any other person.

Transmission fluid is a hydraulic fluid and motor oil is a lubricant. While transmission fluid does have some lubricating properties, it is not enough to sustain an engine. Motor oil is an excellent lubricant, but not such a good hydraulic fluid so it can not be used in a transmission.

Transmission fluid can also be used in power steering systems without harm since that is a hydraulic system, but not motor oil. Never, ever under any circumstances should transmission fluid or motor oil be used in the brake system. It would result in brake failure and do considerable damage to the brake components.