Pontiac 2004 GTO - Manual (Page 209)

{ CAUTION:
Operating the engine with the air cleaner/filter
off can cause you or others to be burned.
The air cleaner not only cleans the air, it helps
to stop flame if the engine backfires. If it is
not there and the engine backfires, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/filter off.
Notice: If the air cleaner/filter 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/filter in place when you
are driving.
Automatic Transmission Fluid
When to Check and Change
The fluid level should be checked monthly, by looking at
the fluid level on the dipstick. A good time to check
your automatic transmission fluid level is when
the engine oil is changed.
See Scheduled Maintenance on page 6-4 for more
information on when to check and change the fluid
and filter.
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