Symptoms
SERVICE AIR SUSPENSION message, the rear sagging overnight, or a compressor that runs constantly. The owner's manual says leveling pauses with any door open, so close everything before you diagnose it.
The fix, step by step
- To repair it, find the leak first (lines, fittings or the air springs) before replacing the compressor.
- Owners say later dual-stage compressors are less likely to overheat, and switching to one needs two new hoses.
- To convert, support the frame, lower the axle (one owner didn't need to remove the shocks), remove the air springs and fit coil springs with upper and lower isolators.
Tools & part numbers
- Jack and stands
- basic sockets
- soapy water for leak checks. Fabtech lists H2 coil-spring and air-bag lift options.
Where to buy the parts
Air suspension compressor (catalog, 2005 H2)RockAuto ↗
Rear air springs (catalog, 2005 H2)RockAuto ↗
Coil springs (catalog, 2005 H2)RockAuto ↗
Hunting a used or discontinued part? Search eBay Motors for AM General Hummer H2 parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.