Manufacturer specifications apply. This page explains concepts only. Torque values, clearances, preload, backlash ranges and procedures vary by axle model and must come from the vehicle or component manufacturer's service information. This directory does not publish repair specifications.
What this service covers
In a full-floating axle, the wheel hub rides on its own bearings on a spindle at the end of the axle housing. The hub bearings carry the vehicle's weight; the axle shaft only transmits torque.
This design is used on most three-quarter-ton and one-ton pickups, and on medium- and heavy-duty trucks. A key benefit is that a broken shaft does not usually let the wheel come off.
Common signs
- Gear oil leaking at the hub or axle flange
- Wheel play or bearing noise
- Overheated hub after a bearing adjustment problem
What the work usually involves
- Remove the axle shaft and inspect splines and flange
- Service hub bearings and seals and set bearing adjustment by the specified procedure
- Reinstall the shaft with new gaskets or seals and check lube level
Steps vary by vehicle and component design. Values and procedures come from the manufacturer's service information.
Vehicles this applies to
Heavy-duty pickups, commercial vans and Class 3–8 trucks.
Key terms
Axle shaft spline
The machined teeth on the end of an axle shaft that engage the differential side gear (and, on full-floating axles, the hub drive flange). Spline count and diameter must match the mating part exactly; worn or twisted splines are a reason to replace the shaft.
Full-floating axle
The wheel hub rides on its own bearings on a spindle that is part of the axle housing, so the housing carries the vehicle's weight and the axle shaft only transmits torque. Common on many 3/4-ton and 1-ton pickups and on commercial trucks.
Wheel-end bearing
The bearings that support the hub on the axle spindle. Heavy trucks commonly use tapered roller bearings, either adjusted using a specified procedure or supplied as pre-set or unitized assemblies. Adjustment procedures come from the axle or hub manufacturer.
Hub seal
The seal at the inboard side of the hub that keeps oil or grease in and keeps water and dirt out. A leaking hub seal can contaminate brakes and lead to bearing failure.
Choosing a shop
- Confirm the shop works on your vehicle class and, for trucks, your axle make.
- Ask what parts they install (new, remanufactured or rebuilt) and what warranty applies.
- Check the listing's verification status and date in this directory.