Hummer H1 biggest tire size: stock and lifted
The biggest tire owners run on a AM General Hummer H1 at every lift height, with the trimming it takes, the wheel specs you need and the lift kits that get you there.
The factory tire was a 37x12.50R16.5, and later trucks used 37-inch tires on 17-inch wheels. Flash Off-Road says a 38x15.5 is the largest you can run on stock wheels without lifting the truck, though you need to watch for rubbing on the suspension at full lock. Taller tires need a body lift: Flash Off-Road reports owners running 39.5s with a 2-inch body lift and no rubbing.
Biggest Hummer H1 tire at every lift
| LIFT | BIGGEST TIRE | WHAT IT TAKES |
|---|---|---|
| Stock | 38x15.5 | Flash Off-Road calls this the largest tire for stock wheels without a lift. Watch for contact with the suspension in tight turns. Load ratings on 38s are lower than on most 37s. |
| 1 in (body) | 40 in (MT/R) | Flash Off-Road saw a 40-in MTR on a turbo diesel with a 1-in body lift, but notes the 40s were load range C against E for the 37s. |
| 2 in (body) | 39.5 in | Owners quoted by Flash Off-Road ran 39.5s with a 2-in body lift and no rubbing. Flash estimates 42s need about 3 in and slight trimming. |
| 4 in (2 in suspension + 2 in body) | Up to 42 in | Predator Inc's recommendation for its combined 4-in kit. |
Hummer H1 wheel and tire specs
| Factory tire sizes | 37x12.50R16.5 LT load range D Goodyear Wrangler MT radial on 16.5-in wheels (1999 brochure) · 37x12.5R17 on 17-in aluminum wheels (offered from 2000; 16.5-in aluminum wheels discontinued by 2002) |
|---|---|
| Bolt pattern | 8x165.1 (8x6.5") |
| Center bore | About 4-3/4 in on the hub-centric factory one-piece steel wheel |
| Wheel offset | 7-in backset on all factory wheels; a GT/Cepek 17x9 is +50 mm |
| Lug thread | 9/16-18 (7/8-in hex nut; a 22 mm socket fits) |
Lift kits, wheels and tires for the Hummer H1
Flash Off-Road reports owners clearing 39.5-inch tires with a 2-inch body lift. Predator's combined 2-inch suspension and 2-inch body lift is meant for tires up to 42 inches. Body lifts need block-off bars to hide the gap at the rear.
Stock-backset wheels and properly routed CTIS lines keep air down and up working on bigger tires.
Fitment comes from owners and specialists; wheel width, offset, trimming and bump stops change what fits. Check clearance at full lock and full flex before you buy. Some links are affiliate links.