
Driving On Grades
Reduce speed and shift to a lower gear before you start down a long or
steep downgrade.
If you don’t shift down, you might have to use your
brakes
so much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to around
45 mph
(70 km/h) to reduce the possibility of engine and transmission overheating.
When towing at high altitude with steep uphill grades,you need to consider
the following information. The lower atmospheric pressure at high altitude
allows your vehicles engine coolant to boil at a lower temperature than at
normal altitudes.
If you immediately turn your engine off after towing at high altitude with
steep uphill grades, your vehicle may show signs similar
to engine
overheating.
To avoid this, let your vehicle operate in a parked position with
the transmission in
“N” (Neutral) for a few minutes before you turn off the
engine. If you do get the overheat warning, see “Engine Overheating” in
the Index.
If you have an automatic transmission, you should use
“D” (or, as you need
to, a lower gear) when towing a trailer. Operating your vehicle in
“D” when
towing a trailer will minimize heat buildup and extend the life
of your
transmission.
If you have a manual transmission and
you are towing a trailer, it’s better
not to use fifth gear. Just drive in fourth gear (or, as you need to, a lower
gear).
Parking on Hills
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.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into “P’ (Park) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are in place, release the regular brakes until the
chocks absorb
the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift to
“P7, (Park), or “R” (Reverse) for a manual transmission.
If
you have a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in
“N7 (Neutral).
Release
the regular brakes.
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.-. -1 To remove the air
cleaner filter on
a gas
engine or a 6.5 liter
naturally aspirated
diesel,
turn the wing
nuts to the left.
Remove the cover and
change the filter.
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Nuid
When to Check and 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
a GM dealership Service Department.
If you do it yourself, be SLIK to follow all the instructions here, or you could
get a false reading on the dipstick.
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How to Add Fluid
Refer to the Maintenance Schedule to determine what kind of transmission
fluid
to use. See “Recommended Fluids and Lubricants” in the Index.
If the fluid level is low, add
only enough of the proper fluid to bring the
level up to the COLD area for a cold check or the HOT area for a hot check.
It doesn’t take much tluid, generally less than a pint. Don’t overfill. We
recommend you use only fluid labeled DEXRON@-111 or DEXRON@-IIE,
because fluids with that label are made especially for your automatic
transmission. Damage caused by fluid other than
DEXRON@-Ill or
DEXRON@-IIE is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as described under “How to
Check.”
When the correct fluid level is obtained, push the dipstick back in all
the way; then flip the handle down to lock the dipstick in place.
Manual Fluid
When to Check
A good time to have it checked is when the engine oil is changed. However,
the fluid
in your manual transmission doesn’t require changing.
How to Check
Because this operation can be a little difficult, you may choose to have this
done at a
GM dealership Service Department.
If you do it yourself, be sure to follow all the instructions here, or you could
get
a false reading.
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, starting a fire. Be sure to get
an accurate reading if
you check your transmission fluid.
Check the fluid level only when your engine is off, the vehicle is parked on
a level place and the transmission is cool enough for you to rest your fingers
on the transmission case.
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Explanation Of Scheduled Mainienance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. Make sure
whoever services your vehicle uses these. All parts should be replaced and
all necessary repairs done before you or anyone else drives the vehicle.
1. ENGINE OIL AND OIL FILTER CHANGE“‘ - ALWAYS USE
SJ3 ENERGY CONSERVING I1 (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS
OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine (e.g.
SAE 5W-30 or 10W-30), see “Engine Oil”
in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
If you have a 3500
HD, lubricate the king pins and king pin bushings,
every
1,500 miles (2500 km) for Maintenance Schedule I, or every
3,000 (5000 km) for Maintenance Schedule 11.
Ball joints and king pin bushings should not be lubricated unless their
temperature
is 10” F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or
they could be damaged.
Also, be sure
to check all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION WITH DEEP LOW
) - Lubricate the
clutch fork ball stud through the fitting
on the clutch housing.
Lubricant must be added “sparingly” to
the fitting, as only .0066 lb.
(.003 kg) is required to lubricate the ball stud surface. Do not add
lubricant more often than the intervals
in the Maintenance Charts. Too
much lubricant will damage the clutch assembly.
4. COOLING SYSTEM SERVICE”’? - Drain, flush and refill system
with new coolant. See “Engine Coolant” in the Index for
the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension clamps).
Remove debris and clean the outside of the radiator and air
conditioning condenser. Wash the radiator neck.
To ensure proper
operation, pressure test.
the radiator and cap.
* An Emission Control Service
?A fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability
of your vehicle.
Be sure any necessary repairs are completed at once. Whenever any fluids
or lubricants are added to your vehicle, make sure they are
the proper ones,
as shown
in this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certification/Tire
label. See “Loading Your Vehicle” or “Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See
the “Recommended Fluid and Lubricants” chart in this section.
Transmission neutral or clutch start switch operation -
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake”
in the Index. Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only
in “P’ (Park) or “N” (Neutral).
On manual transmission vehicles, put the shift lever
in “N” (Neutral), push
the clutch down halfway, and try to start the engine. The starter should work
only when the clutch
is pushed down all the way to the floor.
Steering column lock operation - While parked, try to turn the key to
LOCK in each gear shift position.
With an automatic transmission, the key should
turn to LOCK only when
the gear shift
is in “P” (Park).
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On vehicles with a key release lever, try to turn the key to LOCK without
pressing the lever. The key should turn to
LOCK only with the key lever
depressed.
On
all vehicles, the key should come out only in LOCK.
Parking brake and transmission
“P” (PARK) mechanism operation -
I
Park on a fairly steep hill, with the vehicle facing downhill. Keeping your
foot on the regular brake, set the manual parking brake.
To check the parking brake: With the engine running and the
transmission
in “N” (Neutral), slowly remove foot pressure from the
regular brake pedal. Do this until the vehicle is held by the parking
brake only.
0 To check the “P’ (Park) mechanism’s holding ability: Apply the regular
brake and shift to
“P’ (Park). Release the manual parking brake, then
slowly release the regular brake.
Lap and Shoulder Belts Condition and Operation - Inspect belt system,
including webbing, buckles, latch plates, retractors, guide loops and
anchors. Have
a belt assembly replaced if the webbing has been cut or
otherwise damaged.
Body Lubrication Service - Lubricate all body door hinges with engine
oil. Also lubricate the tailgate, tailgate handle pivot points, and tailgate
mounted spare tire carrier
(if equipped}. Lubricate the body hood, fuel door
and rear compartment hinges, latches and locks including interior glove box
and console doors, and any folding seat hardware. Lubricate the hood safety
lever pivot and prop rod pivot. More frequent lubrication may be required
when exposed to a corrosive environment.
Periodic Maintenance Inspections - Listed below are inspections and
services which should be performed at least twice
a year (for instance each
spring or fall). You should
let your GM dealer’s service department or other
qualified service center do these
jobs. Make sure any necessary repairs are
completed at once.
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Recommended Fluids & Lubricants
NOTE: Fluids and lubricants identified below by name, part number or
specification may be obtained from your GM Dealer.
USAGE
Engine Oil - Gasoline
Engines
Engine
Oil - Diesel Engines
Engine Coolant
Hydraulic Clutch System
Hydraulic Brake Systems
Parking Brake Cables
Power Steering System
Automatic Transmission
FLUIDLUBRICANT
API service SH or SG Energy
Conserving I1 oils
of the recommended
viscosity. The
“SH” designation may be
shown alone or
in combination with
others, such
as “SH/CD,” “SH, SG,
CD,”“SG/CD,” etc. To determine the
preferred viscosity for your vehicle’s
engine, see “Engine Oil” in the Index.
API service CF4SH. The
“CF4SH”
designation may be shown alone or in
combination
with others, such as
“CF-4/SG,” “CE/SH” or “CE/SG,” etc.
The designation may
also be listed in
reverse order, such
as “SH/CF-4.” To
determine the preferred viscosity for
your vehicle’s engine, see “Engine Oil”
in the Index.
Mixture
of water and a good quality
ethylene glycol base antifreeze
conforming
to “GM Specification
6038-M” (GM Part No. 1052753)’ or
approved recycled coolant conforming to
“GM Specification
603%”’ with a
complete coolant flush and refill.
Hydraulic Clutch Fluid (GM Part No.
I2345347 or equivalent).
Delco Supreme
11 @ brake fluid (GM
Part No.
1052535 or equivalent DOT-3
brake fluid).
Chassis Lubricant (GM Part No.
I2346003 or equivalent) or lubricant
meeting requirements of NLGI Grade
2,
Category LB or GC-LB.
GM Power Steering Fluid (GM Part
No. 1050017 or equivalent) conforming
to
“GM Specification 99850 10.”
DEXRON~ 111 or DEXRON~ IIE
Automatic Transmission Fluid.
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USAGE
Manual Transmission: a. 5-Speed with Low Gear
(FWO MT8)
FLUIDLUBRICANT
a. Castrol Syntorq or equivalent
(GM
Part No. 12345871 - 1 gal.)
(GM
Part NO. 12346074 - 1 st.).
b. $-Speed without Low Gear b. Synchromesh Transmission Fluid
(RPO MG5) (GM Part No. 12345349 or equivalent).
Differential:
a. Standard (Saginaw) Front
and Rear Axle
b. Locking
c. 3500 HD Models used
under extreme conditions
Transfer Case
Gas Line a. Axle Lubricant (GM
Part
No. 1052271) or
SAE-8OW-90
Gear Lubricant.
b. Axle Lubricant (GM Part No.
1052271) or SAE-8OW-90 Gear
Lubricant.
c. Axle Lubricant SAE-75W-140
Synthetic Gear Lubricant.
DEXRON~ 111 or DEXRON@ IIE
Automatic Transmission fluid.
Gas Line De-Icer (GM
Part No. 105 15 16
or equivalent).
Column Shift, Transfer Case, Chassis Lubricant (GM
Part No.
Shift Lever, and Propeller
12346003 or equivalent) or lubricant
Shaft meeting requirements
of NLGI Grade 2,
Category LB or GC-LB.
Clutch Fork Ball Stud (5-Speed with Low Gear)
Hood Latch Assembly a. Pivots and spring anchor
b. Release Pawl
Front Wheel Bearings Chassis Lubricant (GM
Part No.
12346003 or equivalent) or lubricant
meeting requirements of NLGI Grade 2,
Category LB or GC-LB.
a. Engine Oil (GM
Part No. 1050109 or
equivalent).
Chassis Lubricant (GM
Part
No. 12346003 or equivalent) or lubricant
meeting requirements of NLGI Grade 2,
Category LB or GC-LB.
Wheel Bearing Lubricant (GM
Part
No. 12346003 or equivalent) or lubricant
meeting requirements of NLGI Grade 2,
Category GC or GC-LB.
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