Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2009 Hummer H3 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Automatic Transmission - Introduction
- Specifications
- Transmission Fluid Temperature Sensor Specifications
- Fastener Tightening Specifications
- Transmission General Specifications
- Fluid Capacity Specifications
- End Play Specifications
- Low and Reverse Clutch Spacer Plate Selection
- Forward Clutch Backing Plate Selection
- Third and Fourth Clutch Backing Plate Selection
- Reverse Input Clutch Backing Plate Selection
- Fluid Pump Rotor and Slide Measurement
- Torque Converter End Play Specifications
- 2-4 Band Servo Piston Pin Selection
- Range Reference
- Shift Solenoid Valve State and Gear Ratio
- Shift Speed
- Transmission Internal Mode Switch Logic
- Line Pressure
- Component Resistance
- Schematic and Routing Diagrams
- Component Locator
- Diagnostic Information and Procedures
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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