Tech Article Title Author Date
Replacing Rear Wheel Bearings Mr. Piggie(mike01s4) 2004

Worked on an A4 1.8tq rear wheel bearing the other day. Maybe some of ya would be interested in this if you need to do it too.....it's not too long of a job, and I opted to pull the whole hub assembly off the car since using a puller on there then trying to press it in would have been an utter PITA without special tools. the only real special tool I used was a press for putting in the new bearing. If you don't have a press, maybe you can take the whole upright and your new bearing to a shop and they can do it for you?

Some parts/tools

  • Bearing kit part number (comes with new bolt) 8D0598625A
  • 10, 17, 19 mm wrenches
  • 5, 8, 14 mm socketed allen wrenches
  • Arbor press for putting new bearing and hub on
  • Penetrating oil
  • Grease for driveshaft's splines
  • Heavy hammer
  • Some proper size cylinders for removing/installing bearings squarely
  • Very fine abrasive pad/sandpaper

I started by breaking the 14mm allen head, collar bolt, in the hub, free while the car was on the ground. You can do it while the car is up in the air with the wheel off, but then you need to put the parking brake on and put a lug bolt on. After that, you can remove the two 8mm allen head bolts holding on the caliper assembly (put parking brake on). Pull the whole brake assembly out of the way. Remove the 3 10mm bolts for the rotor shield and take it off. Remove the ABS sensor's 5mm head allen bolt. Spray some penetrating oil on it and with a flat screwdriver, gently tap it in to the mating surface to make the sensor lift off. You might want to clean the sensor up before reinstalling so it goes in smoothly and doesn't rust to the suspension upright. After that, mark the orientation of the lower camber bolt with it's adjustment washers. This way you probably won't lose your alignment very much when reinstalling. Remove that lower bolt and the upper control arm bolt, the upper stabilizer bar link bolt, and the rear horizontal arm nut. That rear arm nut was a bit of a pain at the last threads. You can use a clamp to keep the joint from rotating as you twist the nut off.

Now, just remove the suspension upright, and spray it up with a lot of penetrating oil and pound out the steel hub. Chances are, you'll get the larger I.D. part of the bearing stuck on the hub shaft. Just take a screwdriver and tap it in between that ring and the hub and you can pry it off easily. Try not to gouge the surface of the hub or any other surfaces as you work on it.

After that, pound out the bearing (direction for removing is towards the outside [Edited] of the car). clean up the surface with a very fine abrasive cloth and press the new bearing in, and watch the orientation of the bearing since it has 2 different I.D.'s due to the stepped portion of the wheel hub. Don't install it backwards! Take some abrasive pad to the shaft of the hub, spray some oil on it and press the hub back in and be sure to have a good backing against the other side of the bearing so you don't accidentally pop the seal or inner race out.

That's about it. For reinstalling, put some grease on the splines of the driveshaft. When putting the upright back on, lubricate the round discs of the lower connection so it slips right in with a tap of the hammer. The 14mm collar bolt needs to be torqued to around 85 ft-lbs + 180 degrees. You can judge for yourself on that 180 degrees though ;) EEK.

Some pictures...







Close-up of bearing. note the stepped I.D.s. (facing outside of car where hub slips into it, the large I.D. is on the outside facing you)

Slipping the upright back in



Clamping the joint for the nut that's tough to remove



8mm allen bolts holding brake assembly on