1996 Ford Mustang Owner's Manual - Page 264

Checking the Automatic Transmission Fluid It is preferable to check the transmission fluid level at normal operating temperature 150˚F-170˚F (66˚C-77˚C), after approximately 20 miles (30 km) of driving. However, if necessary, you can check the fluid level without having to drive 20 miles (30 km) to obtain a normal operating temperature if outside temperatures are above 50˚F (10˚C). With the vehicle on a level surface, start the engine and, while fully applying the brake pedal, move the transmission shift selector through all of the gear ranges allowing sufficient time for each position to engage. Securely latch the transmission shift selector in the P (Park) position, fully set the parking brake and leave the engine running. NOTE: Your vehicle should not be driven if the fluid level is below the low cold reading on the dipstick. Wipe off the dipstick cap, pull the dipstick out and wipe the indicator end clean. Put the dipstick back into the filler tube and make sure it is fully seated. Pull the dipstick out and read the fluid level. When checking fluid at normal operating temperature 150˚F-170˚F (66˚C-77˚C), the fluid level should be within the hot notched area on the dipstick. When the vehicle has not been driven, and the fluid is at room temperature 50˚F-95˚F (10˚C-35˚C), the fluid level should be within the cold notched area. 270