Symptoms
On 1981-and-later trucks, a front axle that won't engage in 4WD, grinding as the hubs try to lock, or hubs that stay locked in 2WD.
The fix, step by step
- With the front on stands, remove the auto hub cover and the internal parts, including the drag sleeve and spring assembly.
- Inspect the bearings and spindle while you're in there.
- Install the manual hub body and dial per the manufacturer's instructions, using the correct spindle-nut hardware.
- Offroad Design sells Warn internal-style hubs that fit all half-ton GM axles and 1977-and-later three-quarter-ton axles, and Yukon Hardcore hubs for 1979-and-later 8.5-inch fronts and Dana 44s.
- Check that the hubs turn freely in FREE and lock in LOCK.
Tools & part numbers
- Snap-ring pliers
- spindle-nut socket
- torque wrench
- grease
Where to buy the parts
Warn internal-style locking hubs, all 1/2T GM axles and '77+ 3/4TOffroad Design ↗Amazon ↗
Yukon Hardcore locking hubs, '79+ GM 8.5 in front & Dana 44, 19-splineOffroad Design ↗Amazon ↗
GM D44 / 10-bolt spindle nut kit (one side)Offroad Design ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Chevrolet/GMC Suburban (1973–1991 square body) 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.