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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission
fluid level is when the engine oil is changed.
Change both the fluid and filter
every 50,000 miles (83 000 km).
See “Scheduled Maintenance Services” in the
Owner’s Manual.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission. Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if
you check your transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
D When outside temperatures are above 90_F (32_C).
D At high speed for quite a while.
D In heavy traffic
--
especially in hot weather.
D While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 180
_F to 200_F
(82
_C to 93_C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50
_F
(10
_C). If it’s colder than 50_F (10_C), drive the vehicle
in THIRD (3) for 3500HD models and DRIVE (D) for
full
-
size van models until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold fluid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine run
at idle for five minutes if outside temperatures are
50
_F (10_C) or more. If it’s colder than 50_F (10_C),
you may have to idle the engine longer. Should the fluid
level be low during this cold check, you must check the
fluid hot before adding fluid. Checking the fluid hot will
give you a more accurate reading of the fluid level.