How To: Replace rear AWD Hub Assembly/Wheel Bearing

[housegsx]

Problem
I'm going to walk through changing out a rear wheel hub assembly or wheel bearing, whatever you want to call it. Generally if they are really bad you can hear them growling when going around a turn. Mine wasn't that bad yet. I was rotating my tires when I noticed a little axial play when grabbing the wheel and tire.


Tools/Parts/etc You'll Need
New hub assembly (I used Timken part # 512181)
Puller
Dead blow hammer
Vice
Torque wrench
Sockets(14mm and 32mm), socket wrench, extentions, etc.
Anti-seize
Rags
Brake parts cleaner


Procedure

Removal
The first thing to do is loosen lug nuts and jack up car. Support it with a jackstand.


Now remove the wheel. Pull out the cotter pin on the axle. While having the parking brake on you may also want someone to step on the brake pedal while you remove the axle nut. You'll need a 32mm socket for the axle nut. After the axle nut is off you may release the parking brake.



Unbolt the entire brake caliper and hang it out of the way. I just used a couple zip ties to hang it from the upper control arm. Remove the rotor. If it doesn't pull off you may slightly tap around it with a rubber dead blow hammer until it breaks free.

At this point the job is either going to go smoothly or be a real pain. You need to get the axle to break free from splines. It won't hurt to lightly tap the end of the axle with a hammer as long as you're not hitting it hard enough to mushroom the threaded end of the axle. If it's not easily sliding out, put the crown axle nut on backwards and screw it on until flush with the end of the axle. Now you need to use this type of puller to push the axle out of the splines. Bolt it onto a few wheel studs, screw it down pressing on the axle. Now you'll have to take your hammer and pound on the handle a little at a time until it comes out. This puller + a hammer generally works better than anything else including a several ton hydrolic press.


Once the axle is starting to slide out of the splines remove the 4 bolts holding on hub assembly. These are located around the CV boot on the back side of the upright. There are 4 14mm bolts that need removed. This is what I used.

[housegsx]

Here is the old part...

If you buy the entire part it will cost around $200 more. It would be easier, but it will cost three times as much to buy the entire assembly. I didn't think that was worth it. You need to press the old part out and press it into the new hub assembly. Don't try to use a hammer to reassemble into the new bearing; you may destroy the new bearing by doing this. When I pressed the hub off the old bearing half of the bearing got stuck on it. If this happens to you, the easiest way to remove it at this point is to use a puller like this.


I didn't have one handy so I put a notch in the old piece of bearing with a dremel or cutoff tool and then tap it with a chisel. It's hardened steel so it will crack and pop off.


Assembly
While I had the part off I decided to replace the wheel studs for peace of mind. You can press them out or tap them out with a hammer. I just used a hammer. I supported the back of the hub when doing this.

You can press the new studs in. I just did it with a vice. I used a long socket to go over the stud while I tightened the vice. A press would be easier.


Now just push the old splined part of the hub into the new hub assembly/wheel bearing. Old and new.

[housegsx]

At this point I cleaned everything; the axle splines, bolt threads, mating surfaces, etc. Use plenty of anti seize when reassembling everything. I used it on the splines, bolts for the hub, axle nut, bolts for the brake calipers, and the new lug studs.

Clean stuff up.



And use plenty of this.

Here are some pics of the new assembly before installation.








Center the parking brake assembly over the upright and center the new hub assembly, pulling the axle through. Screw the 4 bolts in that hold the hub assembly on. Tighten them down to 54-63 ft. lbs.

Slide the rotor on and mount the caliper.



At this point you can set the parking brake again and have someone step on the brake pedal while you tighten down the axle nut. Tighten the axle nut with the 32mm socket to 159 ft. lbs. Put a new cotter pin through the axle and crown nut. You can mount the wheel. Release the parking brake and shake the wheel and tire... Is all the play gone? It should be. Remove the jack stand and lower the car to the ground. Torque the wheel nuts.




That's it. After about 50 - 100 miles you should recheck you lug nut torque. The new studs may stretch slightly or settle further into the hub releasing some of that preset torque.