Front wheel bearing replacement

[spartacus68]

Borrowed my wife’s i3 REx tonight. At 60mph there’s quite a lot of cabin noise. I’ve changed wheel bearings before on other cars so know the tell tale signs. Car is 2015 on 70k miles. Roads are a bit of a mess just now coming out of winter, so suspect it’s front wheel bearings. It’s a GEN 3 bearing, so basically bolts to the hub.

I’ll go for quality parts, FAG, SKF. No idea what BMW use, but chances are it’s a maker like this. I’ll probably replace the lower steering knuckle ball joint too, scrub that, just looked online and that lower wishbone is one unit, so steering knuckle is integral, not bolt on, typical BMW waste. I’ve had the struts out before to replace the rubber gaiters, and know about the top mount, which frankly is a serviceable item given it’s susceptibility to corrosion.

I also have air tools, if it wants to play hard-ball!

I have ISTA so will check out torque values. Anything else to watch out for?
https://www.mybmwi3.com/forum/viewtopic.php?t=17181

 

[spartacus68]

I stripped down the car today, removed front brakes to test the bearings. This is UK car, so O/S spins, but hardly what I would call freely, but it doesn’t rumble. N/S spins freely, but again no rumble. I’m swapping them out as I’ve no confidence they aren’t worn. Mileage is 70k, so 8 years old.

I ordered FAG bearings this afternoon, and Lemforder drop-links that connect to the ARB stabiliser. I suspect the drop links are always an issue when trying to remove. Wouldn’t be the first time I’ve had to cut them off.

Does anyone know what size the hub nut is please and torque value on tightening. The 4 bolts that hold the hub on are T60.

 

[spartacus68]

Hub nut is 17mm Allen key. Just ordered T60 long bit on 1/2” drive for the hub bolts. According to ISTA, BMW use special tool for Torx bolts.

 

[spartacus68]

Away to do this job at the weekend.

Axle driveshaft bolt uses 17mm Allen key socket. I have 1/2” breaker bar and 1 metre extension. From what I can research it uses once only bolts, part number 33406858534.

I’ll be tightening the bolt with the car raised and brakes applied, then lowering the car with wheel on for final torque.

Details here for SKF/FAG bearings. 210Nm + 90 degrees. https://techtips.alleuro.com/wp-content/uploads/2020/10/SKF-Front-Rear-Axle-Nut-Hub-Mount-Lug-Nut-Torque-Spec.pdf

I’ll post pictures once it’s done.

 

[spartacus68]

I’m a fool!

Did the bearings today. For some unbeknown reason I thought this would have a hub bolt. Wrong!

These are basically bolt on bearings. 80Nm + 90 degrees. A breaker bar is essential to do the final torque.

No real issues. All the bolts are accessible without moving the suspension shock. I did however remove the tie rod, and replaced the drop links to the ARB. Mildly satisfying job. Didn’t even need to break out the air hammer.

 

[Marscar]

Hi, did this sort out the booming?
We have something along those lines, noticeably more in the mid to high 60's mph, so I'm wondering whether it's wheel bearings at all (engine mounts???)
We have a 2018 94 REX by the way.