Buick 1998 Century Owner's Manual page 277

Automatic Transaxle Fluid
When to Check and Change
A good time to check your automatic transaxle fluid
level is when the engine oil is changed.
Change both the fluid and filter every 50,000 miles
(83 000 k m ) if the vehicle is mainly driven under one or
more of these conditions:
0
In heavy city traffic where the outside temperature
regularly reaches 90
O F
(32
O
C) or higher.
In hilly or mountainous terrain.
0
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these
conditions, the fluid and filter do not require changing.
See "Scheduled Maintenance Services" in the Index.
How to Check
Because this operation can be a little difficult, you
may
choose to have this done at your Buick 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.
I
NOTICE:
Too much or too little fluid can damage your
transaxle. 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. Be sure to
get an accurate reading if you check your
transaxle fluid.
Wait at least 30 minutes before checking the transaxle
fluid level if you have been driving:
When outside temperatures are above 90°F (32" C ) .
0
At high speed for quite a while.
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