GMC 2003 Envoy - Manual (Page 293)

Driving On Grades Parking on Hlils
Reduce speed and shlit lo a loweT geat before; you start
down a lofl^ oi sleep downgradEt ti you don'l shiH down,
you mlghl have to use your brakes so much !ha! they
would get hot and no longer work well,
Vou can tow in DRIVE {□). You may want to shltt ihe
transmission to THIRD (3) or a tower gear, under heavy
loads oi hilly conditions.
When lowing at high altitude on steep uphill grades,
consider the following. Engine coolenl wHI boil at a lower
tertiperatiLife than at normal attitudes, II you turn your
engine oft immediately after towing at high altitude
on steep uphill grades, ynur vehicle may show signs
Similar I
g engine averheating. To avoid this, let The
engine run while parked [ipnelerabiy on level ground)
with the aiitomatic transmission fn PARK (P) for a
few minutes before turning the engine off. If you do get
the overheat lA/amlng, see
Efjgine Ovefbeating an
p^ge 5-27y
You really should not park your vehicle, with a
trailer attached, on a hllL If something goes
wrongT your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be daTnaged.
Bui if you over have to park your rig on a hill, here's
how to do it.
1. Apply your regular brakes, but don't shift Into
PARK (P) yei. When pgildng uphill, turn your wheels
away from the curb. When parking downhjll, turn
your wheels Into the curb.
2. Have someone place chocks under the trailer
wheels,
3. When the whael chocks are in place, release the
regular brakes until the chocks absorb the load.
A Reapply ihe regular brakes. Then apply your
partting brake, arri then shift into PARK (P).
5. Release the regular brakes.
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