Replacing Front Wheel Hub/Bearing

[Mitch90535im]

So, tell me about the difficulty level of replacing the front wheel hub/bearing please. I understand that there's probably specailty tools involved (that I likely don't have) not to mention lots of torque on the nut.

[shogun]

go to my website below, on the left side you find
links & lots of DIY
go to other DIY links and there to Johan & Sean, detailed write up, E32, but all the same procedure.

[Mitch90535im]

Love it. When all else fails and you don't have the specality tool, use a hammer. Thanks for the link Shogun. Lots of good info there.

[MBXB]

1- 13/16 3/4 inch drive socket for the nut; a 1/2 to 3/4 drive adaptor, a clicker 1/2 inch drive torque wrench that will go over 300 ft-lbs, one 6 foot long 2 inch steel pipe from my wifes hammock set. 1/2 inch breaker bar optional.
and the rest of the tools to remove a rotor.
Final assemble is one guy on the pipe, and one guy listening for the click of the torque wrench. I think the setting was 280-ft lbs.

[Mitch90535im]

1- 13/16 3/4 inch drive socket for the nut; a 1/2 to 3/4 drive adaptor, a clicker 1/2 inch drive torque wrench that will go over 300 ft-lbs, one 6 foot long 2 inch steel pipe from my wifes hammock set. 1/2 inch breaker bar optional.
and the rest of the tools to remove a rotor.
Final assemble is one guy on the pipe, and one guy listening for the click of the torque wrench. I think the setting was 280-ft lbs.



Yours came off without a proper "puller"? Did you use a hammer?

[MBXB]

Used a heat gun on the nut first. Then cracked the nut with a breaker bar and the long pipe. Let things cool down. (1-2 beers) Mounted the puller, put tension on the hub, and used the heat gun on the outside of the hub. As it heated I'd crank down on the puller a little more. After the entire hub was hot enough, it popped off. Had a buddy wearing oven mitts catch the hub.

[leicesterboy15]

I did this job today and thought I'd share my experiences for the novice (like me) DIY'er for future reference.

Overall the job wasn't that bad, I followed the process in the bently manual and on this site:

BMW E34 Website (http://www.bmwe34.net/E34main/Maintenance/Suspension/WheelBearing.htm)

The job was pretty straight forward, I bought the hub with bearing, nut and both dust covers for £170 from BMW, the hub can be bought from ebay for £35 but I didn't look there before I'd bought. Plus I've had issues with ebay parts before and I am only planning to do this once!

In my view the must haves are the socket for the nut (obviously) but also a puller:

Laser 2 or 3 Leg Rev Gear Puller | Screwfix.com (http://www.screwfix.com/p/laser-2-or-3-leg-rev-gear-puller/48634)

and an electric torque wrench, I've got this one:

12V Impact Wrench Digital Display & Torque Config GS/CE | eBay (http://www.ebay.co.uk/itm/12V-Impact-Wrench-Digital-Display-Torque-Config-GS-CE-/270724073250?pt=UK_Home_Garden_PowerTools_SM&hash=item3f08698722)

It makes really easy work of getting the big nut off and torquing it up again. The biggest issue I had was getting the bolt off that holds the brake disc on. I've had this issue before and its a real pain. It was really jammed and heating it up seemed to make no difference and then the inevitable happened - I rounded off the head!! I had to apply loads of heat, made some cuts with a dremmel and used a screwdriver and hammer in the groves I'd cut while applying loads of heat to coax it round and eventually it shifted.

So the process then, all went as per the procedure in the link, jack the car up, remove the dust cap, use the electric torque wrench ad 290nm to loosen the big nut, get a screwdriver behind the brake pad to push the piston back, this moves the pads away from the disc, then remove the caliper (2 x 19mm bolts), suspend it with wire - all straight forward. Next was the brake disc screw (see above) but once this was off the hub came off with some heat and a few knocks with the hammer although the inner race remained in place as described in the procedure. I used a puller on this, I think this was essential because even with the heat shield removed I can't see how you could get behind it with a hammer to get it off, maybe with some heat it might have done but with the puller it came straight off.

Once the hub is totally off clean the mounting surface (replace the rear dust cover if you've got a replacement) and to get the new hub back on I pushed it on with my hands until it was lined up then with a block of wood over the front tapped into place with a hammer until the thread was exposed and I could get the large nut back on, then I did up the nut and this pushed the hub the rest of the way. Once in place fit the caliper and disc, torque up the big bolt with the electric wrench (290Nm) and thats pretty much it. To 'stake' the nut to the axle I used a dremmel to cut down the sides and then I bent it in although I think you could have used a screwdriver and hammer as it seemed soft enough, would have taken more time though. I didn't know what 'stake' meant but its pretty clear when you see it!

With tools and genuine BMW parts I'd say the job cost me about £250 although I had all the tools already other than the socket for the big nut (£15) so it cost me £185. If you used ebay parts you could get the whole job done including the tools mentioned above for about £120.

It took me 6 hours on and off but I reckon its a 2hr job if you don't hit any snags.