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1975 GMC C1500
400ci V8•RWD•AUTOMATIC•gas
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Repairs0Labor558Torque154Fluid7DTC0Battery1Maintenance0Recalls0
Fluid · Rear Differential

Rear Differential

for 1975 GMC C1500 400ci V8 · RWD
Fluid Type
SAE 80W-90 gear oil
Spec: GL-5
Capacity
4qt
3.78 L
Drain & Refill
4 qt
3.78 L
Change Interval
30,000 mi
48,270 km

Notes

12-bolt full-floating rear axle more common with 400ci. Add limited-slip additive if equipped with Positraction

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Other fluid systems on this vehicle

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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