Brake caliper bolts-advice or tips please

[Kristophe]

I'm taking the plunge on changing my right-side CV axle nessisated by my wheel bearing going out. What's ironic is I was able to finally get the 36mm axle nut off after much effort. But now I cannot get the two 16mm bolts loose to remove the brake caliper. But Mercy, I just can't get a good position to really turn or pull the socket wrench and that's compounded by the limited space of the wheel well. I was able to fashion a 4ft breaker bar for the axle nut at least.

I don't have an impact wrench but if that's what it will take.

[admranger]

Those should only be torqued to 110Nm or 81 ft lbs, but they come from the factory with thread locker. Make sure you use thread locker on them when you replace them.

You can use a hydraulic jack to push the breaker bar up but watch that you don't raise the X off the jackstands. Pushing down is usually getting your leg(s) involved...

You are turning the wheels so you have easier access, right?

An impact wrench makes things easier.

[davintosh]

Yes, make sure you are turning the wheels to get better access to those bolts, and use a cheater bar on your wrench. I keep a 4-foot length of iron pipe around for just such projects; sized to fit my 1/2" ratchet & breaker bar.

But if you can swing it, the impact wrench is really the way to go. The most affordable version is the plug-in electric; I got mine on sale from a big-box hardware store a couple of years ago, and it is hands-down the best $40 I have ever spent. Heck, even if I'd spent the $70 on it at full price, it'd still be well worth the admission price! Made me wonder why I didn't buy one years earlier.
Tool Shop 1/2" Impact Wrench Kit at Menards

And if you think those bolts are tough, wait until you get to pulling that bearing out. I just did the left side bearing on mine yesterday and -- whoof! -- that was a job! I used a bearing puller set with the wheel carrier still attached to the strut, but on the other side I may just bite the bullet & pull it off so that I can use a press to get the old bearing out & the new one in.

[Kristophe]

Well it's true the stupid question is the one not asked. I took your suggestions and found I was able to turn the wheels more inward and then able to slip my breaker bar just past the fender. Success!

Now the fun part; removing the axle from the hub. I've read of some using a "hammer and daft"; how exactly? I'm guessing an Autozone hub puller would be just as easy.

[davintosh]

I think you have a long haul in front of you; you'd better do some homework before getting yourself in too far. I started another thread on the topic of wheel bearings, and so far it's collected some good info; you ought to check it out. http://www.xoutpost.com/bmw-sav-foru...aring-r-r.html

I don't mean to discourage you, but this is a big, big job, and you really need to look into all that's involved before you get too far. Once you start pulling the hub off, there is no turning back and driving it to a mechanic for help. The bearing is destroyed when you pull the hub off, so then you need to either replace the bearing in place, or pull the whole wheel carrier off & take it somewhere to get replaced. Then you have to put it all back together. From memory, here are the steps I took to do the job:

1. Raise front end.
2. Remove wheel.
3. Unstake hub nut and remove.
4. Remove brake caliper, hang caliper from frame.
5. Remove brake disk retaining bolt, and remove brake disk.
6. Remove bolts holding wheel carrier to strut.
7. Tap drive axle inward to release from splined hub.
8. Temporarily replace bolts holding wheel carrier to strut.
9. Use slide hammer to remove hub.
10. Remove dust shield/protection plate.
11. Remove ABS sensor.
12. Remove bearing retainer snap ring.
13. Use wheel bearing adapter plates & cups to remove bearing from wheel carrier.
14. Use Dremel tool with cutoff wheel to split bearing race clinging to hub spindle.
15. Replace dust shield/protection plate.
16. Clean up bearing mating surfaces & apply antisieze compound.
17. Use wheel bearing adapter plates & cups to press bearing into wheel carrier.
18. Reinstall bearing retainer snap ring.
19. Reinstall/replace ABS sensor.
20. Use wheel bearing adapter plates & cups to press hub spindle into bearing.
21. Remove bolts holding wheel carrier to strut to allow wheel carrier to move out far enough to reinsert axle end into splined hub.
22. Use special tool to pull axle end into splined hub.
23. Replace hub nut, torque to spec, and restake to the axle spindle.
24. Reinstall brake disk & retaining bolt.
25. Reinstall brake caliper.
26. Reinstall wheel.
27. Lower front end.

That's probably not an exhaustive list, and it just breezes by some of the struggles I've encountered, and the costs. Many of the tools can be obtained through loaner programs, but some can't, and they can get expensive. The Advance Auto store near me had a slide hammer in their freebie loaner program; your Autozone ought to as well. It'll look like this one --> http://www.harborfreight.com/media/c...mage_21847.jpg

Then you'll either need to pull the whole wheel carrier off (have to get the control arms and tie rod off for that) and use a hydraulic press to get the bearing out, or leave the carrier in place and use a set of wheel bearing adapters. I have a hydraulic press, but was able to buy a wheel bearing adapter set from another member here who had just done this job on his X5.
I don't think I would've saved much time or effort by pulling the wheel carrier, but for that you need a some tie rod tools. I got a front end service kit from Advance Auto in case I needed it (similar to this one 5 Piece Front End Service Tool Set ).

But before you can even start on pressing/pulling the bearing out, you need to deal with the snap ring. I already had a very nice Channel Lock snap ring pliers, but it was no match for this monster; I ended up spending $40 on a Lisle heavy duty unit. Bottom-line pricing on Lisle 49200 at ToolTopia.com . Even with that tool, that snap ring was not easy to coax out of there.

And once you get to that point you need to get the ABS sensor out of the way. Mine wouldn't budge. No idea how long it had been in there, but I had to drill it out; another ~$80 for a pair of those (because I know I'll find the same situation on the other side.)

Again, I don't write this to discourage you, just to make sure you know what you're getting into. Do some research & make sure you've got your tools & parts lined up before you start, or this could be a very long, frustrating job for you. If you have any hesitation, at least take the vehicle to a few shops & see what they would charge for the job. Your time and your X5's downtime are worth something.

[Kristophe]

I appreciate the great advice and concern. I actually planned on removing the whole knuckle and taking it to a shop to have the old bearing pressed out/new pressed in. I called him first (mutual friends of the family) and he said they've done BMW bearings before and has the tools and press and to bring it on in. I have a Timken bearing.

I did call around. BMW wanted almost $300 just for the bearing and recommended flange so no doubt they'd charge somewhere north of $900 to do the repair. There's this new "indy" shop I was told about and the owner/main mechanic is actually from Germany and I called to get a quote and never heard anything back. That was disappointing. When I called again I just got the recording. Maybe he had a family emergency. But my bearing got so bad she was dragging and my spedo quit working when I got home so I'd have to have it towed wherever she went. Did I maybe bite off more than I can chew? Likely. If I get stuck along the way I know a mobile mechanic that could come for $60 an hour.

If I'm successful on my own all the credit goes to all you guys and Xoutpost. This has been a tremendous resource. To quote bluerussian "BOOYA!!!"

[davintosh]

$300 for the bearing & "flange"? I'm guessing that would be the hub, which the BMW TIS recommends replacing, but really isn't necessary if you can get the inner race off by other means. It's still perfectly usable.

Check at your Autozone for loaner tools to get the control arms & tie rod off too, as that will be a struggle without them. The tool pictured in the upper left corner is the one that I've found most useful for getting the tie rod & control arm ball joints loose; start by loosening the nuts on each (soak with PB Blaster or other penetrant first) then back the nuts out a bit but leave it on the stud and have the top part of the lever press against the nut instead of the top of the stud to keep from damaging the threads.

Also, the bolts that hold the wheel carrier to the strut are tough ones. I think the torque spec on them is 180 ft. lbs., and since it's a bolt & nut you'll need a wrench on both sides, 22mm I think.

And make sure you have some wire handy that can be used to suspend the brake caliper and drive axle; you don't want either to be hanging unsupported.

Good luck on the project; keep us posted on your progress!

[Kristophe]

Tonight I was able to remove everything but the CV axle shaft was being stubborn (using a hammer and drift to push out from the hub) so I ran to Autozone just before they closed and rented an axle hub puller and wouldn't you know it the brake rotor center flange got in the way (too high) and I wasn't able to use it. Drat. Or else I'd be taking the knuckle assembly to the shop tomorrow during my lunch hour. Now that I think of it it seems like someone posted about the AZ version not fitting.

I think it I'll need a 4lb sledge and more WD-40

[Ricky Bobby]

Yes, that was me that posted about the Autozone "hub puller" not fitting, you need a different loaner part from autozone (I'm assuming you rented the slide hammer from there) See the front wheel bearing thread for more details but this is what you need to rent, and don't return the hub puller you have yet, read on:

OEM/Axle puller (27032) | Loan-a-Tools | AutoZone.com


It's called an Axle puller, loaner part 27032. It's a bit wider in diameter than the Hub Puller, so the flange fits on just fine and you can thread three lug nuts over the hub to secure it. The caveat is that you need the threaded rod in the Hub Puller kit to thread on the axle puller, so that you can thread it in and "push" the axle inwards.


The Kit davintosh posted about from Advance Auto actually includes both flanges, and the threaded rod so its really an all-in-one kit, whereas if you are renting tools from Autozone you need three tools.



Good luck with the bearing/CV job, I did both sides early in the summer and it was definitely a huge job, I have zero impact tools and made do with only buying about 100 bucks worth of tools for the job, I rented the rest. In the Front Wheel Bearing thread referenced above, there is a nice writeup from the E39 forums which is helpful, but again, you really need a set of heavy duty circlip pliers as well to get those circlips out!


And yes, you will need a 4 lb mini sledge (I got mine for 10 bucks from Harbor Freight, love that place!), plenty of WD-40 and anti-seize. God bless you for taking the knuckle off, no way I was going through that trouble, and then having to torque all the control arms at the frame with the vehicle on the ground, wasn't for me. With the 85 dollar wheel bearing adapter kit from harbor freight (use a coupon on it, its 120 normally) you'd be just fine and removing and reinstalling them with the knuckle on the car. Good luck either way and if you need help just let davintosh or myself know, his memory on the job is fresher than mine but I know the job quite well and won't forget it for a while.

[davintosh]

Yes indeed this job is fresh in my memory; it's staring me in the face every time I open the door to the garage:



It's been like that since Saturday; I decided to wait for the ABS sensor to arrive before putting it back on the road. My wife doesn't like driving my car, so isn't terribly happy with me, but she still loves me so there's hope she'll like me again too.