Ram Trucks 2012 Chassis Cab - Diesel Supplement - Manual (Page 128)

To prevent dirt and water from entering the transmission
after checking or replenishing fluid, make certain that the
dipstick cap is properly reseated. It is normal for the
dipstick cap to spring back slightly from its fully seated
position, as long as its seal remains engaged in the
dipstick tube.
Fluid Level Check – Chassis Cab Only
Check the fluid level while the transmission is at normal
operating temperature. This occurs after at least 15 miles
(25 km) of driving. At normal operating temperature, the
fluid cannot be held comfortably between the fingertips.
To properly check the transmission fluid, the following
procedure must be used.
1. The vehicle must be on level ground.
2. Operate the engine at idle speed for a minimum of
60 seconds and normal operating temperature.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the shift lever momentarily into each gear posi-
tion ending with the shift lever in PARK. Make sure the
engine is running at idle speed.
5. Remove the dipstick and determine if the fluid is hot
or cold. Hot fluid is approximately 160°F to 175°F (70°C
to 82°C). This is the normal operating temperature after
the vehicle has been driven at least 15 miles (25 km). The
fluid cannot be comfortably held between the fingertips.
Only use the cold region of the dipstick as a rough
reference when doing initial oil level set after transmis-
sion rebuild or transmission refill.
6. Wipe the dipstick clean and reinsert it until seated.
126 MAINTAINING YOUR VEHICLE