Hi everyone. Been a while since I have had to ask any technical questions about my sons A4 since the great engine swap of 2011. I rode in it the other day and we could not have any type of conversation at speeds anything above 30 mph. I suspected the passenger side wheel bearing but after some dis-assembly and checking this evening it seems the noise is coming from the bearing on the inner part of the shaft.

So here is where I need the help. I have searched threads for the last couple of hours and cant find the part number for this bearing or even the proper name for it. Does this bearing come with the shaft? Any help would be greatly appreciated. This thing is really howling/grinding.

I did find a couple of threads on how to remove the shaft without removing all of the suspension so that was pretty cool.

 

You can either buy replacement ends/ cv joints for the half-shaft from websites like blauparts or ecstuning. When you buy a new half-shaft it comes with new cv joints on each end. Easier to buy a new half-shaft in my mind, though more expensive.

 

if it is grinding, odds are its the wheel bearing. hows the up and down motion of the wheel while it is jacked up? ive had bad bearings before where i thought it was the cv joint and it turns out it was the bearing all along. and audi's are notorious for having bearings go bad.

if you are confident it is the outer cv joint, dont cheap out on the part. get a loebro joint.

 

^This. You definitely don't want to cheap out on CV joints and half shafts. Stay away from the Chinese garbage brands like EMPI and FEQ. Ask me how I know

I've had good luck getting CV joints from Blauparts. If you want to replace the whole half shaft, give Marty a call at Raxles. They only rebuild OEM half shafts and they use better-than-OEM quality parts. They also offer a lifetime warranty, which is more than you get from OEM.

 

The part number you are looking for on the front outer wheel bearing in the steering knuckle is 4B0-498-625 and the OEM Audi part runs 90.02 dollars plus 10.00 UPS ground shipping. To help you make sure it's the bearing and not something else you can turn the wheel slightly and listen for a change in the noise. For example if you are going down a straight road and it's making the noise, but that noise goes away or changes when you turn the steering wheel slightly one or or the other, that is a sympton of a bad wheel bearing.

It is for the bearing only, the cv joint and axle shaft is an assembly all its own and usually makes a different clicking noise when the outer cv joint is going bad, different than a growling noise like a bearing makes.

The inner cv joint is sold as new and more expensive than a reman shaft assembly. The RF axle assembly with inner and outer joints, shaft and both boots is p/n 8D0-407-452-X for 259.53 and there is one left in the US at a couple days away. There are a few choices just for the right side in the aftermarket so having this part number will help you in getting the correct shaft whether it's from us or not.

 

Thank you for the replies. I pulled the wheel off and was ready to replace the wheel bearing the other evening but when I started checking it really seems like the noise is coming from the inner bearing on the shaft. Unless the noise and vibration is reverberating through the shaft to that area I really believe it is in this bearing.

However with that said the noise does change when driving and you turn. That does indicate wheels bearings as said. How much of a coincidence would it be if they were bot bad? As I said before, this thing is really grinding. Nearly unable to speak to each other at speeds over 30 MPH or so.

I will be checking it out further in the morning.

Thanks again.