Braking solution?

Wow, you do have a large pad spot on the disc where is might have been clamped tight while the rotor was way hot. That alone could cause the fluctuations you refer to.
Bedding in may not be able to erase the effects. Worth trying the whole procedure over if you noted any improvement from the first time.

I have new control arms, bushings, pads, rotors, and still have the vibration. It's not much, but it's there. I am suspecting strut mounts...

Mention ball joints and tie rods?
Mileage on these parts? Gotta consider everything.

Got your wheels balanced again too?

Alignment?

What makes you suspect the strut mounts? That's rare.

Originally Posted by E46Mango

did you ever resolve your steering vibrations??

Yup, mine ended up being my driver's side FCAB. I don't seem to notice any vibrations in braking now with the Meyle HDs. I loooove the improved road feel.

Still need to get my alignment done and will do a balance just for good measure, but so far I have no time to do them I wish there was a good alignment shop open on weekends.

56k

Originally Posted by Stinger9

Mention ball joints and tie rods?
Mileage on these parts? Gotta consider everything.

Got your wheels balanced again too?

Alignment?

What makes you suspect the strut mounts? That's rare.

I replaced the control arms recently. If you are talking about the tie-rod ball joints, they are certainly a possibilty. Mileage is at ~150K. Other BMWs I'd owned with a lot more miles did not need tie-rods replaced. So it's an educated guess. But still, a possibility.

Wheels are balanced, alignment is fresh. Again, other BMWs I'd owned had bad strut mount bearings when removed, that's why I suspect them.

I am all ears for other possibilities tough...

Originally Posted by SeanC

I replaced the control arms recently. If you are talking about the tie-rod ball joints, they are certainly a possibilty. Mileage is at ~150K. Other BMWs I'd owned with a lot more miles did not need tie-rods replaced. So it's an educated guess. But still, a possibility.

Wheels are balanced, alignment is fresh. Again, other BMWs I'd owned had bad strut mount bearings when removed, that's why I suspect them.

I am all ears for other possibilities tough...

You're getting the vibration ONLY under braking? Strut bearings should be replaced anyway when you do the struts. Any obvious play in them when unloaded and you move the strut assembly with your hand? And what brand rotors, control arms, bushings, pads? When you removed your wheels, did you sand and clean all wheel to hub mounting surfaces? I could go on and on but lets start with what parts you have and when/how you're experiencing the vibrations

Originally Posted by SeanC

I replaced the control arms recently. If you are talking about the tie-rod ball joints, they are certainly a possibilty. Mileage is at ~150K. Other BMWs I'd owned with a lot more miles did not need tie-rods replaced. So it's an educated guess. But still, a possibility.

Wheels are balanced, alignment is fresh. Again, other BMWs I'd owned had bad strut mount bearings when removed, that's why I suspect them.

I am all ears for other possibilities tough...

Ball joints are good then, but actually check out the tie rods to eliminate that. All cars are not the same, nor exist in the same environment.

It is not strange to get tires balanced, yet they are still out of balance. Can you swap the rears with the fronts? Staggered for you?

Find out how to check strut mounts and check them too. Gotta start eliminating things. (how do you check strut mounts on the car? disconnect the lower end and try to wiggle?)

Originally Posted by E46Mango

You're getting the vibration ONLY under braking? Strut bearings should be replaced anyway when you do the struts. Any obvious play in them when unloaded and you move the strut assembly with your hand? And what brand rotors, control arms, bushings, pads? When you removed your wheels, did you sand and clean all wheel to hub mounting surfaces? I could go on and on but lets start with what parts you have and when/how you're experiencing the vibrations

No obvious movement using hand only, but I don't trust that. Brembos, ZHP arms, Lemforder bushings, OEM pads. Wheel hubs have been cleaned througly before putting new rotors on.

However, I am running with one less wheel nut on the driver's side. Apparently some incompetent mechanic was able to strip the threads. Not sure if this would cause a vibration though.

Originally Posted by Stinger9

Ball joints are good then, but actually check out the tie rods to eliminate that. All cars are not the same, nor exist in the same environment.

It is not strange to get tires balanced, yet they are still out of balance. Can you swap the rears with the fronts? Staggered for you?

Find out how to check strut mounts and check them too. Gotta start eliminating things. (how do you check strut mounts on the car? disconnect the lower end and try to wiggle?)

Next time I'm under the car for suspension work, it will be for new struts/mounts and tie-rods. The vibration doesn't bother me that much to do the suspension work in the near future.

Square setup 225/45/17's all around. Already rotated rears and fronts. No difference.

As far as I'm concerned, the correct way to check the strut mounts is when they are out of the car. I guess, they'll have to wait.

Originally Posted by SeanC

No obvious movement using hand only, but I don't trust that. Brembos, ZHP arms, Lemforder bushings, OEM pads. Wheel hubs have been cleaned througly before putting new rotors on.

However, I am running with one less wheel nut on the driver's side. Apparently some incompetent mechanic was able to strip the threads. Not sure if this would cause a vibration though.



Next time I'm under the car for suspension work, it will be for new struts/mounts and tie-rods. The vibration doesn't bother me that much to do the suspension work in the near future.

Square setup 225/45/17's all around. Already rotated rears and fronts. No difference.

As far as I'm concerned, the correct way to check the strut mounts is when they are out of the car. I guess, they'll have to wait.

Again, when/how you experience the vibration is the most important thing. Also describe the intensity. The missing wheel bolt could cause balancing problems but not exclusively under braking. (if thats in fact when you're feeling it)

Also yes you can't "trust" any hand test, but very serious/obvious problems can AND will show up by simply moving the part with your hand. I've moved control arms and trailing arms by hand before where the bushings were shot. very obvious movement.

I'd be willing to bet your control arm bushings weren't installed correctly and/or are defective. Walk me through the history of the control arms and bushings. Who installed them, how installed, etc.

Get Meyle CABs.

Originally Posted by SeanC

However, I am running with one less wheel nut on the driver's side. Apparently some incompetent mechanic was able to strip the threads. Not sure if this would cause a vibration though.

Actually it's not a nut, but a bolt. With weight of some consequence mitigated by the fact that it's in close to the center rather than out at the edge where normally weights are added for balancing. But not a problem if vibration just under braking.

Ok loving how this thread went to **** after getting hijacked.

Originally Posted by PrecisionX

Ok loving how this thread went to **** after getting hijacked.

Welcome to E46Fanatics. We love you too.

Originally Posted by PrecisionX

Ok loving how this thread went to **** after getting hijacked.

It's called a conversation and we've addressed your issue each time you've posted a question.
And will continue to do same if you jump in again.

You requested pics so I gave them and didn't get much feedback

Originally Posted by PrecisionX

You requested pics so I gave them and didn't get much feedback

In post #21 I wrote: Wow, you do have a large pad spot on the disc where is might have been clamped tight while the rotor was way hot. That alone could cause the fluctuations you refer to.
Bedding in may not be able to erase the effects. Worth trying the whole procedure over if you noted any improvement from the first time.

That was all I knew to say. Won't say more if I don't know more.
In the future if you think we've ignored you, push again. We're guys and it gets a little rough sometimes. But the board solves lots of problems too.

Originally Posted by PrecisionX

You requested pics so I gave them and didn't get much feedback

- Your rotors are worn out, you should replace your rotors
- Your pads are likely worn out as well, you should replace your pads

Seeing the scorching, deep scours, and the very visible lip indicate that your rotors are worn out. To fix that on a brake lathe would require too deep of cutting. Your pads at this point have grooves in them as you see on your brake rotor, so getting new rotors only wouldn't be good. If you would like suggestions on different rotors/pad combinations, there are lots of threads on this.

I personally recommend EBC pads and EBC rotors, they design their rotors to work with their pads hand-in-hand from the factory. EBC rotors are a little difficult to come across compared to others, but they're of great quality.

I'm jumping in here quite late, but; steering wheel vibration under braking can be several things or a combination of several things. From the photos you posted, your rotors are worn and most likely warped/have excessive run-out, which will cause steering wheel vibration under most braking conditions. In 2 of the photos, it even looked as though the rotors were scorched, that is that they were excessively heated. This can be caused by a caliper that doesn't release when the brakes are left off, keeping one or both pads in tight contact with the rotor. Since it looks like they were warmed up pretty good, I wouldn't spend the money to have them turned. There are many different rotors out there by many good makers. For several years I've used cross-drilled rotors from R1 Concepts. With those rotors I've used both Metal Master pads and R1's full ceramic pads. I prefer R1 ceramic pads, the metal masters are great once they are warmed up a bit. In the past I've also used Padig pads and ATE cross-rilled rotors. The Pagid pads I used to use are hard to come by now and when you do find them, they are quite expensive. If you look, you will find many solid, cross-rilled, slotted and cross-drilled & slotted rotors for your car, all by good names. There are quite a few here that do not like cross-drilled rotors for street use, though there is nothing wrong with them. They actually perform better. There are also many different pads. Pads can be inexpensive to expensive, low dusting or high dusting, metallic, semi-metallic, carbon and ceramic. Everyone has their favorites.
If you replace your rotors and pads, make sure that you clean and lube the guide pins and use never-seize compound where the pads touch the holders and disc brake quiet to glue the pads.
Something else to consider, replacing the rubber brake hoses with stainless steel hoses. They again are some here that feel it is a waste of time and money to use stainless steel lines for street use, however there are several advantages; you many well never have to replace them, they do not "swell" and by not swelling keep constant pressure for overall better braking performance.
Now as to other things that can lead to steering wheel shake under braking; worn lower control arm outer ball joints, worn/torn front lower control arm bushings, worn tie rods, worn sway bar links, bent and/or flat spotted wheels, badly worn tires.
Most of these items are fairly easy to check.
But from the photos, for right now, I'd be replacing the rotors and the pads. They've seen their better days.

Originally Posted by tomoyer

I'm jumping in here quite late, but; steering wheel vibration under braking can be several things or a combination of several things. From the photos you posted, your rotors are worn and most likely warped/have excessive run-out, which will cause steering wheel vibration under most braking conditions. In 2 of the photos, it even looked as though the rotors were scorched, that is that they were excessively heated. This can be caused by a caliper that doesn't release when the brakes are left off, keeping one or both pads in tight contact with the rotor. Since it looks like they were warmed up pretty good, I wouldn't spend the money to have them turned. There are many different rotors out there by many good makers. For several years I've used cross-drilled rotors from R1 Concepts. With those rotors I've used both Metal Master pads and R1's full ceramic pads. I prefer R1 ceramic pads, the metal masters are great once they are warmed up a bit. In the past I've also used Padig pads and ATE cross-rilled rotors. The Pagid pads I used to use are hard to come by now and when you do find them, they are quite expensive. If you look, you will find many solid, cross-rilled, slotted and cross-drilled & slotted rotors for your car, all by good names. There are quite a few here that do not like cross-drilled rotors for street use, though there is nothing wrong with them. They actually perform better. There are also many different pads. Pads can be inexpensive to expensive, low dusting or high dusting, metallic, semi-metallic, carbon and ceramic. Everyone has their favorites.
If you replace your rotors and pads, make sure that you clean and lube the guide pins and use never-seize compound where the pads touch the holders and disc brake quiet to glue the pads.
Something else to consider, replacing the rubber brake hoses with stainless steel hoses. They again are some here that feel it is a waste of time and money to use stainless steel lines for street use, however there are several advantages; you many well never have to replace them, they do not "swell" and by not swelling keep constant pressure for overall better braking performance.
Now as to other things that can lead to steering wheel shake under braking; worn lower control arm outer ball joints, worn/torn front lower control arm bushings, worn tie rods, worn sway bar links, bent and/or flat spotted wheels, badly worn tires.
Most of these items are fairly easy to check.
But from the photos, for right now, I'd be replacing the rotors and the pads. They've seen their better days.

No offense, but the highlighted statement in bold tosses all credibility out the window. All... of... it. And rotors for all intents and purposes don't warp.

Originally Posted by tomoyer

From the photos you posted, your rotors are worn and most likely warped/have excessive run-out

For the record, warped rotors are a relatively rare condition that can really only occur in the following conditions:

1. Very hot rotors and suddenly going through a very deep puddle

2. Bent wheels, and the rotor eventually conforming to the wheel wobble from heat

Most brake vibration comes from hot spots and excessive pad buildup in one location. When you get cementite on your brake rotors, it's near impossible to remove without simply shaving off a layer of the rotor.

The best way to prevent wheel vibrations is to not brake too hard, and if you do brake hard, do not hold the brakes at a complete stop. You'd need to go get some good heat buildup for this to happen, and I'd argue that you're more likely to get that problem in mountainous areas...or if you drive like a complete asshat all the time