🧪Fluid Capacities
Hummer H3 Fluid Capacities
All fluid capacities for your Hummer H3: engine oil, coolant, transmission fluid, brake fluid, power steering, and more.
Quick Answer
The Hummer H3 requires multiple fluids maintained at specific levels. Engine oil, coolant, transmission fluid, brake fluid, and power steering fluid all have different capacities depending on your engine and model year.
2006-2010
2006-2010Engine Oil4.0 - 6.5 quarts (varies by engine)
Coolant (total system)6.0 - 10.0 quarts
Transmission Fluid3.5 - 4.0 quarts (drain & fill) / 7-9 quarts (total)
Brake FluidDOT 3 or DOT 4 — ~1 quart for full flush
Power Steering FluidATF or manufacturer-specific — ~1 quart
Windshield Washer~1 gallon
Notes
- →Never mix different types of coolant — flush completely when changing brands
- →Transmission fluid should be checked with the engine running and at operating temperature
- →Brake fluid absorbs moisture over time — replace every 2-3 years regardless of mileage
Frequently Asked Questions
- How much coolant does a Hummer H3 hold?
- The Hummer H3 cooling system holds 6-10 quarts total depending on the engine. A drain-and-fill replaces about 50-60% of the coolant. For a complete flush, you'll need the full capacity amount.
- What type of transmission fluid does a Hummer H3 use?
- The Hummer H3 transmission fluid type depends on whether it's an automatic or manual transmission and the model year. Automatic transmissions typically use ATF WS, Dexron VI, or manufacturer-specific fluid. Manual transmissions use 75W-90 gear oil.
- Does a Hummer H3 have power steering fluid?
- 2015+ Hummer H3 models with electric power steering don't use power steering fluid. Older models with hydraulic power steering use ATF or manufacturer-specific fluid — check your owner's manual.
- What brake fluid does a Hummer H3 use?
- Most Hummer H3 models use DOT 3 or DOT 4 brake fluid. DOT 4 has a higher boiling point and is preferred for performance driving. Never use DOT 5 (silicone-based) in a system designed for DOT 3/4.