problems galore - brakes and more
 

I've just about had it. 2 more problems i found today :( I was driving home after work and had to hit the brakes fairly hard on the freeway. I noticed that the steering wheel jereked a little bit to the right then stopped. This is not noticed when gradually applying the brakes under normal conditions. I was able to repeat this a couple more times by tapping the brakes quickly.

I just recently (last week) replaced my old worn out rotors with new OEM ones and likewise my old OEM pads with Axxiss deluxe.

I did the bedding procedure. Everything seemed fine, but maybe I just didn't notice this then. I was getting a lot of noise from the pads scraping the rotors but I have driven about 100mi since then and the noise seems to have gone away. Is this at all normal being that I have not driven on the new brakes much yet?

So after I parked the car I started exploring a little more - to my shagrin I found that my passenger side CV boot had torn pretty bad and thrown grease all over the inside of the wheel, great. Can't wait to do this job again... I just replaced the driver side not long ago. The apple doesn't fall to far from the tree. They weren't kidding when they told me to just replace both sides. I knew it was going to go sometime soon because i could see it starting to crack - I was just hoping to go a little longer on it lol. This must have happened today.

I don't think the brake issue and cv boot things are related. I'll probably check the wheel lug nut torque first, then work my way around each wheel to inspect the rotors and each caliper to make sure the pads are sitting even on the rotors.

The brake pedal feels pretty normal, maybe a little on the soft side.

Can anyone please help me out here or steer me im the right direction? I'm not totally sure what I should be looking for in regards to the braking problem. I'm guessing since the wheel jerks to the right then the problem is probably in the front driver side wheel? I would think that this might be due to the passenger side caliper getting more pressure and gripping the rotor better? I can see the zinc has worn off the rotors on both sides tho? Ugh I am so frustrated and the CV boot was just the fucking cherry on top.

we350z call me if you still have my #

it sounds like the caliper braket may be coming loose and binding on the rotor. Especially when applying the brakes. Since you had to remove the braket when replacing the rotor, this could be the reason one wheel is binding (pulling). Check it out, as this is not a safe circumstance!

Thrust arm bushings are probably also starting to weaken....

Thanks guys I am going to check the fronts out and re-torque carrier brackets and guide bolts but the pads might not be totally bedded just yet. I also didn't realize that I should avoid holding the brake at stops during the break-in/bedding period for the first 200-300mi (however I was aware of this during bedding procedure). I guess this can warp the rotors and make them uneven from the heat. So I will try to put in N and use the e-brake at stops and avoid hard braking for a little while. I thought everything was set after doing the initial bedding procedure. There is still some residual zinc shit on it as well - but its obvious that both sides are compressing and scraping it off. Also checked that there are no kinked lines and no flluid leaking from the calipers or brake lines. Hopefully everything will get situated if it's not already. I'll be worried about it if its still doing this after the initial break-in period is over. I guess it's a good sign that there is no jerking/shimmying/wobbling when doing light breaking on the streets.

Won't hurt to check brake fluid level as well, perhaps I am low.

Can inspect these and tell? Car has 68Kmi but of course is almost 9 years old too.

I would also flush the brake fluid. You may have a tiny air bubble. I suspect that may be the reason for the panic stop pulling. I have seen this a few times. I use a Motive power bleeder and love the thing.

CV joint, that looks like a tad of work.

CV boots
 

Very, very important, you must replace both sides at the same time to avoid the problem. My local BMW dealer advised that after a friend of mine experienced the same problems as you. By replacing just one side the waer and tear is uneven and you end up having to replace the cv's again.

Well it's going to end up about the same time. I have probably less than 400mi on the driver side.

Did you notice it pulling any time before you changed the brakes?

No - everything was even. I'm going to check everything out tomorrow.

I feel your pain man, I'm in the same boat as you right now. I just replaced my pads and rotors last month and I'm starting to get a vibration during braking. I took the car to my mechanic last week to have all the front suspension parts replaced (ie. control arms, tie rods, sway bar end links, ball joints) because I thought they might have something to do with the vibration and although they did reduce it its still there. While doing the work last week I get a call from him telling me my passenger side cv boot is torn to shit and grease is everywhere... great. I just replaced the drivers side 3 months ago and now I got to do it all over again.

Sorry to hear about your problems, don't let get you down, once you make your repairs it should be good for a while.

How long do brakes last, I have 34,000 and they seem fine?

cv boots
 

I dont know where you got your cv boots from but FCP Groton got them for cheap and they are the same as BMW dealer, but way cheaper I bought both sides for under $250.00

Uhh... you can get a kit from Crevier or Morristown for like $35 per side...

we350z, I am no expert, but it sounds like there is something wrong with some work/breaking in you did on the brakes. If it drove and stopped fine before your brake job, then something may be installed incorrectly or not torqued to the correct specs. If you can't figure it out, have the car inspected by a good indy shop or dealer and have them flush the brake fluid.

Also, if you did hold the brakes when they were hot, some pad material may have transferred to the rotor, which can cause vibration and grabbing issues. If you are sure all of the bolts are correctly torqued, then try the bedding process again to remove any debris from the rotor. That may help.

Good luck.

Cool. I will do as prescribed :) Would I be able to visually see the debris on the rotor? If everything checks out otherwise I may just try bedding procedure again. If all else fails and this behavior continues after 200-300mi point I will likely do a flush and/or have it inspected by my indy mechanic.

I don't think you would be able to see pad residue on the rotor in all cases. I am not positive though. Someone who knows better may chime in on this one.

I just keep going back to the fact that if your X was stopping fine before the brakes change, then something you did must be off a little bit. I changed all 4 rotors and pads and broke them in with Dave Z's recommendation and everything worked like a champ. No noise, vibration or pulling at all. I used Centric rotors though, they don't have that think zinc coating on them. It could be a crazy coincedence and you have an issue with a suspension component, but I would stick with the brakes first.

When you do the rebedding process, you can use the brakes after you do the 8 (or whatever #) stops, just don't sit at a stoplight the brakes held. That is when the pad material will transfer. You can also use the steptronic trans mode to downshift and instead of braking.

OK. I don't recall holding the brakes because I was cognicent of the fact that this transfer may occur. I should have however used ebrake/N and downshifting. I may not have allowed sufficient time on highway for cool down (only about 10 minutes). The brakes did still seem very hot when i put the car in the garage, but then again its Phoenix.

You are right about it stopping fine before i changed the brakes. Something must be off, I agree. In my mind it can be one of two things:

1) something in front not torqued right (i.e. carrier bracket buckling)
2) something uneven on rotor/not bedded in properly yet

Regardless. I need to jack the front up to do a temporary saran wrap fix on the CV boot until my replacement part comes in later this week. I am going to do a full inspection. Calipers seem to be on pretty good though when I try pushing them with my hand.

You could also check the caliper guide pins (if you removed them) and the rattle clips???

Yep removed both guide pins up front and the top ones in the rear. I am going to check all of that. If that's all good then repeat bedding procedure. If that dosen't work and the problem still persists after 200-300mi then I will take it into the indy mechanic. I may have them do the CV boot anyway since it's a PITA.

OK - I took the wheels off the front and checked the entire system. Everything is torqued fine rotors are straight and true and I don't see and foreign material on the rotors and the pads look to be lying perfectly flat for the most part.

I have noticed on these Axxis deluxe pas that the inboard front pads are bevel cut somewhat - perhaps this is causing the problem somehow since the entire pad is not yet gripping the rotor? Is this normal for new pads? I would think this would mean less surface area on the pad initially until they are worn down some.

So I am not sure what to do here. Redo bedding procedure perhaps? Could the rears be causing this jerk? I have been very good about not holding the brakes at stops. Maybe I should wait until i have some more miles on it. It looks like most of the zinc crap is off the rotors now as well.

I was thinking if this problem persists i may remove the front outboard pads and compare them - maybe i have a defective pad? Beyond that I have no idea - I will prob have to have the indy check it out.

Anyone got an idea here? I am lost :(

2 things you might wanna check.

1. check if control arm or tension strut bushing/ball joint is gone on both sides. You can lift up the front end and shake wheel with hands at 3 o'clock and 9 o'clock positions. See if there is any play.

2. check if caliper is seized. drive around for a while and see if one side brake rotor is hoter than another side.

Cool - easy enough, I will check that out. If steering wheel is jerking right does that mean in both potential cases that the problem would lie on the passenger side? Or I am thinking rather #1 pass side bad suspension component and #2 driver side seized caliper.

Whats the likelihood of each with 8.5 year and 68Kmi?

What might cause a seized piston in the caliper? Is compressing the caliper with the c-clamp bad for it? Nothing was mentioned to that effect in hayaku's DIY.

exactamundo. If your 2000 x5 has had no replacements of tension rod bushings or thrust arm bushings than its time to replace them, get some ball joints too if the fluid is leaking.

I don't recall seeing any of those in the past service records for the vehicle. Are these babies easy to replace? I don't recall seeing anything leaking but I will check again in more detail. I'm sure there is a DIY on the front page.

Shit - I should have done this while i was in there before I guess. I think I now where the tension rod bushings are (the rubber deals on the bottom of the vertical thin metal bar going from strut tower brace to half-axle assembly, right)? Where are the thrust arm busings? Any Pics?

Whats the best way to test this, with a digital thermometer lol?

I would say just feel with finger tip. (don't touch it directly though.) if it's seized, the difference should be obvious.

I think he meant the tension strut (aka front control arm). number 6 in this link http://www.realoem.com/bmw/showparts...21&hg=31&fg=05

It could be the bushing(#7) or ball joint(#15)

The rubber seal outside the piston might be worn and grease with dirt from your cv boot might sneak into there already. When you use c-clamp to push piston in, you should clamp on the brake pad and it's okay to do it.

Well I did it on the pad when the caliper was still mounted to help get it off the router, but then i had to compress it a little bit more without the pad on to get it flat enough. I think I put the round floating part of the clamp in the middle of the piston. Maybe that did f it up? Didn't seem like it and the others are fine i did it the same way. DIY didn't mention anything special here and I had done this once before when I did the cv boot repair without issue. They were all a little bit dirty, I tried to clean them off with air compressor air gun tool as best I could.

Is there a certifiable way to tell if it's the caliper? Maybe the heat thing?

OK - I'll try that too. If it's seized it will not be gripping at all? What about compressing the piston with the c-clamp then pressing the brake pedal to see if it tightens up?

Can the calipers be switched side to side to see if the problem moves? Worst case scenario how much is a new one or can they be repaired? What about aftermarket, perhaps something stronger? Probably won't work with the rotrs I got.

After reading a bit I found some interesting info and things to try on an e46 site:

http://forum.e46fanatics.com/showthread.php?t=571942

Some techniques that are definately worth trying. I assume the piston can seize either in the open or closed position? Also answers my question about whether or not the caliper can be repaired, it seems that there are seal kits for them and they can sometimes be salvaged. Whether or not I would want to roll the dice on a safety device is another thing lol.

Also searching on this site for provides a wealth of information, a lot of people who have had a simialar issue such as this.

IF I do have a frozen piston - is it possible I warped the rotors already? Both fronts or just if one side was dragging? If so can they be machined or sanded down and re-used? I can't imagine that this few miles could have done anything yet...

Can i determine this using my digital micrometer?

Well i haven't done my tests yet but i am thinking frozen caliper makes the most sense here. everything was fine before. I did some searching and at least replacing with a reman unit wont be that pricy. About $55 after core refund here. Repair kit is about $25 and probably not worth the time and frustrations. If it ends up being the problem gives me a good reason to bleed and install SS lines maybe.

So where can I get some SS lines?

I just tried shaking the front wheels with the front end on stands. They seem pretty solid. The pass side seems like it might be have a tiny bit more play but really for the most part is really firm.

How much is too much play? Should it be noticeable? Obvious?

One thing I have notices is when i drive the car and go over a speed bump with the passenger side there is some squeaking sounds. I don't think the pass side is doing that.

I am going to do the other tests that have been mentioned in my other thread.