GMC 2003 Sierra - Manual (Page 400)

When to Check and Change
A good Hme to chack your eulomatic tnansmisslon fluid
level is when ihe engine oH is changed.
Change bolh the fluid and filter every &0,000 miles
(B3 000 km) ii the vehicle’s GVWR Is over &.S00 or if
the vehicle is mainly driven under one or more of these
condilions:
■ In heavy city tnaffic where Ihe oulside temperature
regulady reaches (ЗгХ) or higher»
\ In hilly or mounlalnous terrain,
> When doing frequent trailer towing.
* Uses such as found m taxi, police or delivery
service.
V your vehicle's GVWR is noi over S.600 and you do
not use your vehicle urtder any of thase conditions,
change the fluid and filter every 1СЮ.ООО miles
066 000 km).
Sea Pafl A: Scheduied Maintenance Services on
page S-4.
Automatic Transmission Fluid
(Except Aliison Transmission)
Because this operalion can be a little difficult, you may
choose to have this done at ihe dealership service
department.
If you do It yourself, tm sure to follow all the Inslruclions
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
part or exhaust system parts, starting b fire.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission fluid.
Wail 3i least 30 minutes hefore checking the
iransmiE&ion fluid level if you have been driving:
* When outside temperatures are above 'SO^F (52^C).
\ At high speed for quite a while.
% In heavy traffic - especially in hot weather.
■ While pulling a trailer»
To get Ihe right reading, the fluid should be at normal
operating temperature, which is ISOT ro
2 O 0 'T
(32'’C to 93"CJ.
How to Check
5^25