Want to run bigger tires on your stock-height 1988–1998 GMT400 1500? Here’s what will fit without lift or cutting.
Stock Tire Size on GMT400 1500:
- 2WD C1500: Usually 225/75R15 or 235/75R15
- 4WD K1500: Usually 235/75R15 or 245/75R16
Maximum Tires Without Lift (2WD C1500):
The 2WD C1500 has less fender clearance than the 4WD. At stock height:
- 235/75R15: Stock fitment, no issues
- 245/75R15: Works but tight at full lock
- 265/75R15: May rub inner fender slightly at full lock – may need minor trimming
- 285/75R15: Rubs significantly – not recommended without level or spacers
Maximum Tires Without Lift (4WD K1500):
The K1500 sits slightly higher from the factory and has better clearance:
- 265/75R16: Works on most 4WD K1500s at stock height
- 285/75R16: Works on some K1500s but may need torsion bar crank
- 31x10.50R15: Popular choice for the stock K1500 – fits well
Wheel Offset Matters:
Running wider tires without rubbing often depends on wheel backspacing:
- More backspacing = tire moves inward = less fender contact
- Less backspacing = tire moves out = potential rubbing on frame/UCA
For Best Fitment:
The free torsion bar crank on the K1500 gives you 1–1.5" of front lift and lets you run significantly larger tires.
BFGoodrich All-Terrain T/A KO2 – Great AT tire choice for the K1500 in common fitment sizes.
What’s the biggest tire you’ve squeezed onto your stock GMT400? Share your experience!