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4-53
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine off.
If you do get the overheat warning, see ªEngine
Overheatingº in the Index.
Parking on Hills
CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People can
be injured, and both your vehicle and the trailer
can be damaged.
But if you ever 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) yet, or into gear for a manual
transmission. When parking uphill, turn your wheels
away from the curb. When parking downhill, turn
your wheels into the curb.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P), or
REVERSE (R) for a manual transmission.
5. Release the regular brakes.
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4-54 When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don't
overfill), engine oil, axle lubricant, belt, cooling system
and brake system. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you're trailering, it's a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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5-4
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved in
the procedure. Put an automatic transmission vehicle
in PARK (P) and a manual transmission vehicle
in NEUTRAL (N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter, or accessory power outlets, if you have this
option. Turn off all lamps that aren't needed as well
as radios. This will avoid sparks and help save both
batteries. In addition, it could save your radio!
4. Open the hoods and locate the batteries. Find
the positive (+) and negative (
-) terminals on
each battery.
CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing this,
and some have been blinded. Use a flashlight if
you need more light.
Be sure the battery has enough water. You don't
need to add water to the ACDelco Freedom
battery installed in every new GM vehicle. But if
a battery has filler caps, be sure the right amount
of fluid is there. If it is low, add water to take
care of that first. If you don't, explosive gas
could be present.
Battery fluid contains acid that can burn you.
Don't get it on you. If you accidentally get it in
your eyes or on your skin, flush the place with
water and get medical help immediately.
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5-20
CAUTION:
Changing a tire can cause an injury. The vehicle
can slip off the jack and roll over you or other
people. You and they could be badly injured.
Find a level place to change your tire. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put an automatic transmission shift lever in
PARK (P) or shift a manual transmission
to FIRST (1) or REVERSE (R).
3. Turn off the engine.
4. Put the wheel blocks at the front and rear
of the tire farthest away from the one
being changed. That would be the tire on
the other side of the vehicle, at the
opposite end.
The following steps will tell you how to use the jack and
change a tire.
Removing the Spare Tire and Tools
The jacking equipment you'll need is stored inside the
plastic jack cover which is behind the front seats, either
on the center of the wall (extended cab) or on the
passenger's side of the wall (regular cab).
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6-18
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading on
the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission. 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
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90F (32C).
At high speed for quite a while.
In heavy traffic
-- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at
normal operating temperature, which is 180F to
200F (82C to 93C).Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above
50F (10C). If it's colder than 50F (10C),
drive the vehicle in THIRD (3) until the engine
temperature gage moves and then remains steady for
10 minutes. Then follow the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting for
eight hours or more with the engine off and is used only as
a reference. Let the engine run at idle for five minutes if
outside temperatures are 50F (10C) or more. If it's
colder than 50F (10C), you may have to idle the engine
longer. Should the fluid level be low during a cold check,
you must perform a hot check before adding fluid. This
will give you a more accurate reading of the fluid level.
Checking the Fluid Level
Park your vehicle on a level place. Keep the
engine running.
With the parking brake applied, place the shift lever
in PARK (P).
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6-65
Name Usage
TRL TRN Not Used
TRR TRN Not Used
TRL B/U Not Used
VEH B/U Vehicle Back
-Up Lamps
RT TURN Right Turn Signal FrontName Usage
LT TURN Left Turn Signal Front
HDLP W/W Not Used
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Not Used
LT HDLP Left Headlamp
RT HDLP Right Headlamp
FR PRK Front Parking Lamps
INT BAT I/P Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel
Pump Module, Oil Pressure
ABS Anti
-Lock Brake System
ECM I Engine Control Module Injectors
BTSI Brake
-Transmission Shift
Interlock
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6-66
Name Usage
B/U LP Back
-Up Lamps
A/C Air Conditioning
W/W PMP Not Used
HORN Horn
IGN B Column Feed, IGN 2, 3, 4
RAP Retained Accessory Power
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging IGN 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking LampsName Usage
IGN C Starter Solenoid, Fuel Pump,
PRNDL
HTDSEAT Not Used
HVAC HVAC System
TRCHMSL Not Used
RRDFOG Not Used
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
HAZLP Hazard Lamps
VECHMSL Vehicle Center High
-Mounted
Stoplamp
HTDMIR Heated Outside Mirrors
ATC Transfer Case (Four
-Wheel Drive)
STOPLP Stoplamps
RR W/W Not Used
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Short Trip/City Scheduled Maintenance
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7-8
The services shown in this schedule up to 100,000 miles
(166 000 km) should be performed after 100,000 miles
(166 000 km) at the same intervals. The services shown
at 150,000 miles (240 000 km) should be performed at
the same interval after 150,000 miles (240 000 km).
See ªOwner Checks and Servicesº and ªPeriodic
Maintenance Inspectionsº following.
Footnotes
The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
# Lubricate the front suspension, ball joints, steering
linkage, parking brake cable guides, propshaft splines,
universal joints and brake pedal springs.+ A good time to check your brakes is during tire
rotation. See ªBrake System Inspectionº under ªPeriodic
Maintenance Inspectionsº in Part C of this schedule.
** Drive axle service (see ªRecommended Fluids and
Lubricantsº in the Index for proper lubricant to use):
Locking Differential
-- Drain fluid and refill at first
engine oil change. At subsequent oil changes, check
fluid level and add fluid as needed. If driving in
dusty areas or towing a trailer, drain fluid and refill
every 15,000 miles (25 000 km).
Standard Differential
-- Check fluid level and add
fluid as needed at every oil change. If driving in
dusty areas or towing a trailer, drain fluid and refill
every 15,000 miles (25 000 km).
More frequent lubrication may be required for
heavy
-duty or off-road use.