Chevrolet 2007 TrailBlazer Owner's Manua page 524

(e) Make sure the safety belt reminder light and all
your belts, buckles, latch plates, retractors, and
anchorages are working properly. Look for
any other loose or damaged safety belt system
parts. If you see anything that might keep a safety
belt system from doing its job, have it repaired.
Have any torn or frayed safety belts replaced. Also
look for any opened or broken airbag coverings,
and have them repaired or replaced. The
airbag system does not need regular maintenance.
(f) Lubricate all key lock cylinders, hood latch
assembly, secondary latch, pivots, spring anchor,
release pawl, rear compartment hinges, outer
liftgate handle pivot points, rear door detent link,
roller mechanism, liftgate handle pivot points, latch
bolt, fuel door hinge, cargo door hinge, locks,
and folding seat hardware. More frequent
lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.
(g) Inspect hoses for cracks, chafing, leaks, kinks,
and proper installation.
524
(h) Change automatic transmission fluid and filter
if the vehicle is mainly driven under one or
more of these conditions:
− In heavy city traffic where the outside
temperature regularly reaches 90°F
(32°C) or higher.
− In hilly or mountainous terrain.
− When doing frequent trailer towing.
− Uses such as found in taxi, police, or delivery
service.
(i) Drain, flush, and refill cooling system. This
service can be complex; you should have
your dealer/retailer perform this service. See
Engine Coolant on page 414 for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap, and filler neck. Pressure test the cooling
system and pressure cap.
(j) A fluid loss in any vehicle system could indicate
a problem. Have the system inspected and repaired
and the fluid level checked. Add fluid if needed.
(k) If you drive regularly under dusty conditions,
inspect the filter at each engine oil change.
(l) Visually inspect belt for fraying, excessive
cracks, or obvious damage. Replace belt if
necessary.