1998 GMC SIERRA differential

How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
~
to remain in your vehicle for 5 years or 150,000 miles I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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1 Short Trip/City Maintenance Schedule -- Gasoline Engines I
4:::: Drive axle service (see "Recommended Fluids and
Lubricants"
in the Index for proper lubricant to use):
0 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
0 3500 HD Models with applications requiring
heavy-duty
or off-road use.
extreme overload/trailer towing conditions and
high-speed (above
45 mph or 70 km/h) conditions
for extended periods of time must have the drive axle
fluid changed every
30,000 miles (50 000 km).
See "Recommended Fluids and Lubricants" in
this section.
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Long TripMighway Maintenance Schedule =- Gasoline Engines
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 “Owner Checks and Services” and “Periodic Maintenance Inspections” 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, kingpin bushings,
steering linkage, transmission
shift linkage, transfer case
shift linkage, parking brake cable guides, rear driveline
center splines, front axle propshaft spline and brake
pedal springs. Ball joints and kingpin bushings should
not be lubricated unless their temperature is 10°F
(- 12°C) or higher, or they could be damaged.
+ A good time to check your brakes is during tire
rotation. See “Brake System Inspection” under “Periodic
Maintenance Inspections”
in Part C of this schedule.
‘+‘K Drive axle service (see “Recommended Fluids and
Lubricants”
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.
0 Standard Differential -- Check fluid level and add
fluid
as needed at every engine oil change.
3500 HD Models with applications requiring
high-speed (above 45 mph or 70 kndh) operation
for
extended periods of time must have the drive axle
fluid changed every 30,000 miles
(50 000 km).
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USAGE
Automatic
Transmission
Key Lock
Cylinders
Linkage
I
Chassis Lubrication
Front Wheel
Bearings
Differential,
Front and Rear
Axle
FLUIDLUBRICANT
DEXRON@-I11 Automatic
Transmission Fluid.
Multi-Pur ose Lubricant,
Superlube
L (GM Part
No. 1234624 1 or equivalent).
Lubriplate@ Lubricant Aerosol
(GM Part No. 12346293 or
equivalent) or lubricant meeting
requirements
of NLGI # 2
Category LB or GC-LB.
Chassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements of
NLGI # 2, Category LB or
GC-LB.
Wheel Bearing Lubricant meeting
requirements
of NLGI # 2,
Category GC or GC-LB (GM Part
No. 1 OS 1344 or equivalent).
Axle Lubricant (GM Part
GL-5 Gear Lubricant.
NO. 1052271) or SAE 8OW-90
USAGE
Differential, C3
(HD3500)
Trucks With
Dana Rear Axle
Transfer Case
Windshield
Washer Solvent
Front Axle
Propshaft Spline,
Rear Driveline
Center Splines
and Universal
Joints
One-Piece
Propshaft Spline
(Two-Wheel
Drive with Auto.
Trans
.)
FLUIDLUBRICANT
SAE 75W- 140 Synthetic Gear
Lubricant (GM Part
No. 12346 140) or equivalent.
DEXRON@-111 Automatic
Transmission Fluid.
GM Optikleen@ Washer Solvent
(GM Part
No. 105 15 15)
or equivalent.
Chassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of
NLGI # 2, Category LE or
GC-LB.
Spline Lubricant, Special
Lubricant (GM Part
No. 12345879) or lubricant
meeting requirements of
GM 998530.
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