GMC 1995 Jimmy Owner's Manual page 254

While reassembling the air cleaner assembly, ensure that the air cleaner
cover tabs are fully inserted into the slots in the air cleaner housing. On the
4.3L (VIN W) engine, also make certain that the PCV air tube is properly
seated in the left hand valve cover.
Refer to the Maintenance Schedule to determine when to replace the air
filter.
See "Scheduled Maintenance Services" in the Index.
NOTICE:
If the air cleaner is off, a backfire can cause a damaging engine
fire. And, dirt can easily get into your engine, which will damage
it. Always have the air cleaner in place when you're driving.
Automatic Transmission Fluid
When to Checkand Change
A good time to check your automatic transmission fluid level is when the
engine oil is changed. Refer to the Maintenance Schedule to determine
when to change your fluid. 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 GM 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.
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