Front Wheel Bearing Replacement
 

After chasing a rattle on my right-front corner for years and replacing everything at least once, I bit the bullet and replaced the whole airstrut yesterday but the problem remains exactly the same. Im am nowleft with the wheel bearing/bearing housing.

I cannot find any how to posts about this and it is not something I have done on any car.

Has anyone else on here?

The car has done 280,000miles so I'm surprised they have lasted so long anyway (assuming it is the bearing).

This is the part..
https://www.ebay.co.uk/sch/i.html?_f...nkw=4E0498625D
will the hub part that the brake disk/wheel bolts to need pressing out/in?

Original Audi bearings last a spectacularly long time compared to other stuff I used to work with. 200K is not at all uncommon.

The bearing is a bolt-in component, but you are correct that the hub needs pressing out of the old one and then back in to the new one. The inner race will come with the hub as you remove it - the usual trick with that is to carefully grind a slot in to the race and then split it with a chisel. The bearing is carefully designed to make it impossible to use a bearing splitter.

Assuming you have access to a hydraulic press then that bit is fairly straightforward. Unfortunately getting the bearing off the car is not, as it is steel in an alloy upright and so galvanic corrosion usually makes it something of an ordeal. Normally I will remove the entire upright so I can put it in the bench vice. I will use the bolts as drifts to remove the old one since they are replaced anyway. Normally I'll cut the exposed thread off (thats obvious when you see it) and then unscrew the four bolts a turn or two, then support the strut well and just beat on the bolt heads until the bearing starts to move. Most of them I've done would be impossible to do on the car as you just can't get enough swing on a hammer.

That said, a bearing would usually groan or rumble rather than rattle. Have you tried the inner tie rod?

Thanks MikkiJayne, I see, thanks for sharing your knowledge - It sounds a bit much for me with no workshop/garage and with it bein winter, but I might see in Spring.

Yes, I replaced the tie-rod assemblies twice, greased the rack and adjusted preload. Did all the arms once and single ones thereafter.

I see from motortalk.de early A8s had a recall and they put 2 blobs of grease where the bearing housing mates with the upright due to microscopic movements.

Attachment 22496

I would be astounded if, after 13 salty winters, the bearing has any movement whatsoever in the upright! More likely it is jammed in there so tight with mixed metal corrosion it will take a sound beating with Mjölnir to get the damn thing out :ROFL: Definitely not a job for the road side in winter.

I reassemble them with aluminium anti-seize grease to prevent them corroding quite so badly again.

I did the front wheel bearings on my old B6 A4 which is a very similar setup. The bearing housings were stuck well and truly to the aluminium uprights. IIRC they only seem to go into the upright 5mm or so but that's enough to make em a real pain to remove.

I managed to remove them whilst still on the car with the use of a fairly heavy and long (to get the momentum) slide hammer bolted to the hub. I did half expect at the time that the hub would come out first but they never did. They needed the use of my works 20t press to get them out. Not saying it needed all 20t but they certainly didn't come out without a fight.

Galvanic corrosion, ya gotta love it,...... Or maybe not.

You know I never thought of a slide hammer. The first time I did one of these bearings I didn't have a slide hammer and so never changed my techique after I got one.

If it went through the centre of the hub and pulled on the back of the bearing, rather than pulling on the hub it would be sure to get the whole thing out, assuming its heavy enough. I might try that on the next one +++

Thanks for the info.
https://www.youtube.com/watch?v=obtM__aJ9Yc
While a D4, it is similar and this is a slidehammer example.

https://www.autodoc.co.uk/mapco/13835694
It's £97 for a fully assembled hub/bearing but the brand is not SKF/FAG or similar, it is MAPCO.

They also do a the hub separately for £50 which could be pressed onto a top tier bearing by third party engineering services.

Had a.knocking rattle on mine a few years ago and it turned out the be top suspension mounts worn and knocking against metal sometimes. That's the mounts at the top of the uprights where it comes through into the top of the front arch / wing. Replaced the mounts.and all noises went!

Thanks AM8tey - where are these mounts? The top of the strut is a machined aluminium casting with three hollow centring 'spikes' that bolts with three large bolts onto the space frame/turret. If you meant this casting on the strut then it was replaced with the new strut assembly - or is there something up in the wheelarch?

I think Neil might mean the D2. The D3 air strut is different though as its all one assembly.