Which fluid is the only fluid checked when the engine is running?
Which fluid is the only fluid checked when the engine is running? Transmission fluid Transmission fluid has to be checked with the vehicle in park or neutral and the engine running to be accurate. Many transmissions come with a "lifetime" fluid that should never need replacement, but checking it periodically will ensure proper transmission function. How do you check the fluid level in a car? The fluid level must be checked by raising the car and accessing the fill plug next to the transmission pan. The car must be raised sufficient to safely access the area. How do you check...