Rear Differential

for 2021 GMC Sierra 1500 3.0L I6 Duramax Diesel · RWD

Fluid Type

75W-90 synthetic gear oil

Spec: GM Spec 9985115 or API GL-5

Capacity

3.5qt

3.31 L

Drain & Refill

3.5 qt

3.31 L

Data quality

Book-style estimate

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Notes

RWD configuration, rear differential only. Use GM limited-slip additive (19299549) if equipped with locking or limited-slip differential. Service if towing or severe duty.

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Other fluid systems on this vehicle

Automatic Transmission

12 qt

Washer Fluid

1.2 qt

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