dbias

Changed out my left front wheel bearing today to eliminate a slight growling sound that was speed dependent. Started out a couple months ago as a slight growling at 30 mph and above. As time went on it became audible at lower and lower speeds. Had the day off and all parts finally came in so I gotter done.
The ordering of parts was the most difficult part of the job. ALL websites have the old part number and the wrong picture for the part. I twice ordered what the Audi dealership said was the correct part according to my VIN only to get an email a couple days later saying the part is no longer available, but the second time the dealership asked for the vin again and emailed me back that the part had been superceded. The correct part number is 8W0-498-625 and fits 2016 - 2020 A4 and several other models. Part was 159.00 shipped free and includes the 4 hub bolts and Axle bolt.
The website pictures show the bolt holes being equal distance from each other both top and bottom. The correct part has bolt holes on the bottom that are considerably wider apart than the top two and caused me concern when I opened it as it didn't match all the pictures of the part. (This widening of the bolts on the bottom actually made them easier to get to as it helped to clear the bottom ball joints)
I've easily done a dozen wheel bearings in my years of automotive ownership and this was actually one of the easiest I've done. Having said that I do have a 20 ton shop press, a 10 lb slide hammer hub puller and of course a full set of triple squares (only need a 10 and 12) from prior VW/Audi work. Only thing i had to buy was a 19 mm hex attachment for my breaker bar. Older axle bolts were 17mm.
After watching several YouTube videos to see if this would be any different I came up with my own method. Audi says to remove the entire steering knucle and press the bearing and hub out and back in off the vehicle. Not necessary at all.
I cracked the lug bolts and axle bolt loose on the ground and got the wheel off. Next was removing the two caliper bracket bolts and this is where the most significant difference from other wheel bearing jobs came into play. Caliper has mostly metal brake lines that are attached to a bracket in the back of the steering knuckle. Two 10 triple square bolts hold it in place.



Removing these allow the caliper to be safely hung from the spring. I removed the abs sensor for more movement but its not necessary.
Next I loosened the 4 12 triple square bolts about 1/3 the way out and attached the slide hammer hub puller and pulled the rotor and hub off in one piece as the rotor was stuck and I didn't feel like hammering on it. After about 30 blows the rotor and hub came off and the shocks loosened the rotor. The loosening of the 4 bearing bolts assisted in loosening it and resulted in just having to remove the bolts and taking the old bearing out easily. This brought me to this beautiful sight. Steering knuckle still on the car and not having to remove the axle itself.

The outer bearing race stuck to the hub as most do and I stuck a chisel behind it to remove. Cleaning and greasing and pressing hub into new bearing lead to reinstall in reverse order.

BR18

I think I follow you up to replacing the bearing that I assume slides over the axle. How do you press the hub back on? I've only done wheel bearings on a BMW e36 and the bearing was either pressed in with adapters and threaded stock followed by the hub the same way or the hub and bearing were a unit and pounded into place and drawn tight with the axle nut.

dbias

the hub will need to be pressed into the bearing before putting back onto the car. Make sure that the back of the bearing is supported by a disk that covers not only the small race but the bigger one too. If the old bearing doesn't fall apart I've seen some use it to support the bearing. Other wise all the pressure from the hubs friction with the smaller race it slides into will damage the bearing but if the inside and outside races are supported equally there will be no pressure to damage the bearing. I have the 20 ton press and all the disks to do the job so for me it wasn't hard to do. Some shops will press the hub in for you.
the axle shaft will slide right into the bearing and hub easily. Make sure you clean both the axle shaft and the steering knuckle well before installation of the new bearing

SMac770

A kit like this makes it easy to press the hub into the new bearing: You just put the hub flange in a vice, set up the bearing and press, hand tighten with a 1 1/4" wrench while counter holding with a 1 1/2" wrench; takes no force to push it in.
Others use any other form of press, but it's all about how you support the two pieces to make sure it seats square and you don't jack anything, like the dark magnetic ring on the bearing.

BR18

I've got a kit like that from Harbor Freight, Made doing a rear bearing on my BMW much easier.

minmet

Heard annoying whining noise today. Probably need to change the wheel bearing. looking at the parts. On the Audiusaparts site, for 8W0-498-625 you give above, it says wheel bearing and hub assembly. I would think it’s an assembly with the a new wheel hub pressed on a wheel bearing according to the name. It’s just the wheel bearing, then? Not a pre-assembled wheel bearing/hub combo? Thanks!

SMac770

Audi still using people with a lack for absolute accuracy to produce their documentation it seems.

So there's four involved piece here: the bearing, the hub, the bearing bolts, and the axle bolt.

"In the beginning" for the B9 A4 and A5, there was 8W0 498 625 as a repair kit (thus the "98") that included all those pieces for one side on the front, and 8W0 598 607 as a repair kit that included all those pieces for one side on the rear. Additionally, there was 8W0 598 607 A for the RS models. These parts are all disco, but you might still find them around.

For the front kit, 8W0 498 625 was apparently dropped around Sep 1 '17 and replaced by 8W0 407 607 A. But at that time, the A4 was dropped from the 607 A applicability list. Still there for the A5 and many other vehicles. Doesn't make a lot of sense as the A4 and A5 use the exact same wheel bearing housings (knuckle, spindle, whatever). The catalog shows that currently you'd have to order the four pieces individually for the A4 today: 8W0 407 625 G bearing + 8W0 407 613 hub + 4x WHT 006 966 bearing bolts + 8E0 407 643 A axle bolt. Whether or not the hub is pre-pressed in the 607 A kit, no idea.

For the rear kits, they seem to still be out there, but have been dropped since Apr 30 '18. Four individual pieces again, same bolts, but bearing is 8W0 407 625 J and hub is 8W0 501 652 D. Then again, what's really different about bearing rev G vs rev J? The applicability seems overlapping. And if the bearing really is the same thing, then would not the hub also be? The B8 used the same bearings and hubs on all four corners.

Wish Audi would realize it's actually important to have accurate parts information.

minmet

Thank you, SMac770? That’s very detailed and clear. Wish they still sell that pre-pressed combo kit. It would have made the change much easier.

SMac770

Well, you can still find it out there. It's still a current part (as long as we're talking about the front) for other vehicles, and there's no reason it shouldn't still be listed for the type 8W as far as I can tell.
https://www.genuineaudiparts.com/oem...bly-8w0407607a

Pressing a hub into the bearing is easy; getting the old hub out sucks. But dropping the bearing and hub by a shop and letting them get it out for a 20 (though that's the guy at the shop down the road that I know kind of thing) is a lot better than buying a new hub that you don't really need.

minmet

The one 8W0407607A you referred to is for newer model's rear axial. And the genuineaudiparts site has lots discrepancy compares to audiusa parts site. I even found more items they listed quite differently. Now understand even more what dbias said "The ordering of parts was the most difficult part of the job.". All well, I will just get the aftermarket parts to get by with and ditch it later.