Does anyone have any helpful info on replacing a rear wheel bearing on a 99' A4? .. is this somthing i can do my self? what will i need for tools? .. any help is greatly appriciated.

 

You need a press to take the old bearing off and put the new one on. I did not have a press but took my spindle off and took it to someone to put the bearing on for me- cost about $15 in labor. Don't know what a shop would charge to do a wheel bearing. If you do it yourself you will most likely need to have it aligned, so if you're calling around and getting prices for the wheel bearing job ask if they are aligning it too. I'd say it they will replace the WB and do an alignment for less than a $100 (plus the cost of the bearing) I would do it.

 

Here is a DIY
http://www.audiworld.com/tech/wheel47.shtml

I had mine done, I supplied the bearing and the shop charged me $195(2.5 hours labor I think) - don't think they did an alignment but they also didn't remove the spindle from the car. Its a real PITA but if you have the time and tools go for it.

I also think that $100 for both the install and alignment is nuts - you pay $70-$80 for just the alignment alone. You can get the bearing for under $50 at purems.com

 

Its a very easy DIY, litterally like 3 bolts on the rear suspension, and rotor and you can remove the hub w/bearing. Then like they said take it to a shop with your new bearing and they should be able to easily remove and install the new one. Then bolt the hub back in. I didn't even use the write up for this one, jack the car up take the wheel off and just look at everything in there, it's pretty self explanitory.

 

I did mine myself as well (on a B6 though, not sure how different it is). It took me a while because I live in northern Ontario and there is a lot of salt used in the winter so a lot of the pieces were stuck together due to corrosion. I bought a 20 ton shop press and a spring compressor (I installed coilovers at the same time). The tools probably cost me less than labour would have cost at a shop.
Here are a few pics of the job.

 

On the main 'hub' piece, one of the sway bar nuts, doest seem to have a head?. . . there is a 'cap' ending on it? . .. any ideas how to get it out?