what trans fluid
Transmission fluid is a slippery liquid that acts as a lubricant for all of the moving parts inside your transmission. In an automatic transmission, this fluid also serves as a coolant and a viscous fluid that transmits power from the engine to the transmission. A variety of fluids are used for different transmissions. Automatic transmissions use something called â shockingly â automatic transmission fluid. Manual transmissions use a variety of oils: regular motor oil, heavyweight hypoid gear oil or even automatic transmission fluid in some cases. Your owner's manual will tell you what your transmission calls for.