Four-Wheel Drive; Front Axle; Rear Axle - GMC CHEVROLET Silverado 1500 2021 Owner's Manual

3. Turn the ignition on.
For vehicles not equipped with the Stop/
Start system:
1. Install the negative battery cable clamp
to the negative battery post.
2. Tighten the negative battery cable nut.
3. Turn the ignition on.

Four-Wheel Drive

Transfer Case
When to Check Lubricant
Refer to Maintenance Schedule 0 408 to
determine when to check the lubricant.
1. Fill Plug
2. Drain Plug
To get an accurate reading, the vehicle
should be on a level surface.
If the level is below the bottom of the fill
plug (1) hole, located on the transfer case,
some lubricant will need to be added. Add
enough lubricant to raise the level to the
bottom of the fill plug (1) hole. Use care not
to overtighten the plug.
When to Change Lubricant
Refer to Maintenance Schedule 0 408 to
determine how often to change the
lubricant.
What to Use
Refer to Recommended Fluids and Lubricants
0 417 to determine what kind of lubricant
to use.

Front Axle

When to Check Lubricant
It is not necessary to regularly check the
front axle fluid unless a leak is suspected or
an unusual noise is heard. A fluid loss could
indicate a problem. Have it inspected and
repaired. This service can be complex. See
your dealer.
Vehicle Care
Do not directly power wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or drive axles and should be
replaced.

Rear Axle

When to Check Lubricant
It is not necessary to regularly check the
rear axle fluid unless a leak is suspected or
an unusual noise is heard. A fluid loss could
indicate a problem. Have it inspected and
repaired. This service can be complex. See
your dealer.
Do not directly power wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or drive axles and should be
replaced.
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