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2021 GMC SIERRA 3500HD
6.6L V8 L8T•4WD•AUTOMATIC•gas•turbo
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Repairs0Labor507Torque3518Fluid10DTC1253Battery1Maintenance0Recalls0
Fluid · Coolant

Coolant

for 2021 GMC Sierra 3500HD 6.6L V8 L8T · 4WD
Fluid Type
Dexcool 50/50
Spec: DEX-COOL
Capacity
27.5qt
26.01 L
Drain & Refill
24 qt
22.7 L
Change Interval
150,000 mi
241,350 km

Notes

Orange extended-life coolant. Total capacity includes block, radiator, and heater core. First change at 150k, then every 5 years/150k.

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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 Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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