The 1988–1998 GMT400 trucks have a factory nose-down rake, especially the 4WD K-series. Leveling gives the truck a better stance and allows larger tires. Here are your options.
The Free Option: Torsion Bar Crank (4WD Only)
The K1500/K2500 4WD GMT400 uses torsion bar front suspension. The torsion bar adjuster bolts are located under the cab. Simply tightening these raises the front 1–2" for free. This is the most popular “free mod” on OBS 4x4 trucks.
Torsion Bar Crank Steps:
- Locate the torsion bar adjuster bolt (under the cab, rearward of the torsion bar crossmember)
- Measure current front ride height (fender to ground)
- Tighten the adjuster bolt clockwise (raises front)
- Check and recheck height – aim for level or slightly nose-high
- Get an alignment afterward
Torsion Bar Cranking Limits:
Don’t raise the front more than 2–2.5". Beyond that, you’ll run out of shock travel and accelerate CV/axle wear on 4WD trucks.
For 2WD GMT400:
The 2WD uses coil springs up front. Leveling requires drop spindles (lower the spindle to raise the front) or replacement coil springs.
After Leveling:
Always get a front alignment after cranking the torsion bars. Caster and camber change. Budget $80–$120 for a front alignment.
Rough Country 2" Leveling Kit for 2007–2018 GM 1500 – For reference on the later GMT900/K2XX torsion-bar builds with similar spacer options.
Tire Clearance After Level:
A 1.5–2" level on a stock K1500 GMT400 typically allows:
- 31" tires: No rubbing
- 33" tires: May require minor trimming at full lock
What level have you got on your GMT400? Share your tire size and clearance!