I'm almost done converting my 2WD XJ to 4WD. The front axle I pulled from a junkyard is off a 1999 model, and according to this article it comes with the "760X axle shafts and hubs." What exactly does this mean? Because unfortunately it is missing the differential-side shaft and u-joint, as well as the entire wheel hub/bearing assembly, which brings me to my next question.

Are the wheel hub assemblies interchangeable between 2WD and 4WD axles? Is there a hole with splines hidden somewhere in there that will accept a 4WD axle u-joint? I mean, as long as the spline count is the same.

Last question... if I have to buy a new hub, do I need to replace both hubs? Will only replacing one cause any problems?

 

2WD & 4WD hubs are the same. When I bought my wheel hub, the guy at the parts store said 2WD & 4WD had the same parts number. The axle shafts are what's different. I bought a used hub from a guy with a Wrangler (which was 4WD) and it worked perfect. As for the spindle, it will easily pop out the back of the hub. Just tap it with a hammer. So keep your old hubs and reuse them when needed.

 

There were two different hubs available for the 99 model year. It depends on if the axle has cast or composite rotors. I think the early 99s had cast rotors and the later 99 and on had composite rotors.

 

Yeah, I forgot to mention my jeep is a 92. So he's probably right..

 

Full cast = 3 1/16" overall height

Composite = 3 3/16" overall height

 

Late 80's & possibly early 90's used 2 different styles on the front. The 4WD is unit bearing & 2WD used a rotor with bearings (like most all rwd passenger vehicles).