Excessive Wear in Front Tires

[slemmer]

Thanks Guys for the input. I put all new tires on my car, new pads and rotors on all 4 corners and the shimmy is gone! Upper and lower control arms were done about a year ago.

Stephen, do you remember where you read that post or write up about the loading and tightening? I had my front shocks replaced about 5 years ago, and I think my front tire wear became more noticeable then....this might be why I am getting excessive wear Iabove and beyond normal.

Thanks again guys!

James

Hi James, no, I don't recall where I found that tid bit of info but I was doing the same thing as you were through searches on the Net. What I did was I had the front on jack stands then with the lower shock bolts loose I used a pump jack to compress the lower components upwards till it bottomed out then tightened. Double check the wheel on level ground with a vertical level to confirm you have negative camber and you're good to go.

Stephen

[jimmythefish]

Question 1: my shimmy was mainly coming through the steering wheel when braking under higher speeds (above 55 mph). As time carried on the shimmy was beginning to be noticeable during driving around 50-60 mph, but mild through the steering wheel. Because my upper and lower control arms were replaced approximately 1.4 years ago, I knew they were fine, my front tires were replaced about the same time as the control arms but were showing significant outer edge tire wear (which just annoys me when I put about 9K on these continentals and showing that much wea)r. So, I replaced all 4 tires to start over. The tire replacement helped the mild shimmy at around 50-60mph, but braking shimmy/judder was still present. Replaced all 4 corners rotors and pads and the shimmy/judder is gone.

Now I am working to determine the best method to deal with my tire wear, which I think is more than what is characteristic for this car (I have owned this car over 10 years and put 80K on it). So my first move is to make sure everything is correct in the front, hence my inquiry to Stephen (thanks for the reply!). After I make sure that I have everything correct for the car, then I may start to modify either with camber plates and/or taking the car out of spec to decrease tire wear on the outside fronts and inside rear without ruining the driving characteristics.

However, I have a 5K road trip coming up and will watch the tire wear with the car “spec”, and then consider my next move. I highjacked this old thread because it was appropriate for my situation and I wanted to Include my experiences.

Thanks to everyone for your help I will report back after I have more information.

[racer2086]

Just because the control arms were replaced 1.4 years ago doesn't mean they are ok. All of your symptoms point to control arms: shaking under braking, shaking driving, tire wear.

If those control arms were replaced with cheapo ones or not torqued down under load, then the bushings may have torn and are causing all your problems.

Additionally, I replaced my thrust arms 3.5 years ago with Lemforder, torqued them down under load, and the driver's bushing has already torn and is leaking fluid and the passenger side is worn. Confirmed by the mechanic that rebuilt my transmission. These cars are VERY hard on those upper arms. Hard on all of them really.

[Frankie]

...Replaced all 4 corners rotors and pads and the shimmy/judder is gone.

This reflects my experiences exactly. Common wisdom faults suspension bushings, when in fact it's the brake rotors.

Now I am working to determine the best method to deal with my tire wear...I may start to modify either with camber plates and/or taking the car out of spec...

Good luck. I have caster plates on my car. No difference.

I have concluded excessive tire wear is simply a fact of life with this car. Like it or lump it. I only install cheap tires because I have to buy new every year @ 12K miles. Expensive tires would make no sense. I had similar experiences with my 840Ci but was able to get slightly more mileage (about 15-17K miles). However, I do have the E38 Sport suspension which probably plays a role in the shorter tread life. I hear non-Sports can get over 15K. Lucky bastards.

[jimmythefish]

Just because the control arms were replaced 1.4 years ago doesn't mean they are ok. All of your symptoms point to control arms: shaking under braking, shaking driving, tire wear.

If those control arms were replaced with cheapo ones or not torqued down under load, then the bushings may have torn and are causing all your problems.

Additionally, I replaced my thrust arms 3.5 years ago with Lemforder, torqued them down under load, and the driver's bushing has already torn and is leaking fluid and the passenger side is worn. Confirmed by the mechanic that rebuilt my transmission. These cars are VERY hard on those upper arms. Hard on all of them really.

Excellent point Racer2086, I should have been more clear about the control arms, myself and my mechanic personally inspect the control arms several times during this time. Secondly, I use Lemforder control arms as replacement parts...that does not discount that Lemforder cannot fail just as quickly as cheapo versions. Since I have a collection of cars, I am fortunate to have a qualified mechanic come to my house....my point in saying this is that he comes by often and we check things often. You are very correct, these cars are heavy and are hard on control arms and front tires. My point for continuing is discussion is that my car seems to be wearing front tires more than I am accustom to....meaning that perhaps something more is going on which is why I continue to report and investigate.

[racer2086]

For Jimmy, I just want him to know that while replacing the brake rotors with new may have smoothed things out, I would not be surprised if he develops the shimmy again. The rotors are covering up the real problem, which is bad control arm bushings.

The difference is that when the bushings are bad, any tiny runout in anything -- be it tires, brake rotors, suspension -- is magnified. Thus, parts within normal limits for typical cars with healthy suspension, cause a weak bushing to shake. You replace the "offending" part with new and think "wow I fixed the problem." 3 months later, the shake is back either from normal wear in the parts you replaced or some other source.

I am sitting in the same situation as you Jimmy -- my exact experience now. I started getting the shake a year ago. I replaced brake rotors, felt great for a few months and the shake came back. Then I replaced my tires, which made things feel great for a couple weeks, but then the shaking came back again in the morning until things "warmed up". I tried bedding the brakes again thinking there were deposits on the pads. Nope no help. Car was in getting the transmission rebuilt and he confirmed the bad control arm bushings while it was on the lift. He also confirmed that my steering box is bad with tons of play in it (I knew this). So I'm going to have to get the box rebuilt and replace the arms. In fact, the slop in the box may be wearing out the arms prematurely. So I blew plenty of money on tires I didn't need and time wasted replacing brakes.

Unfortunately (and I talked with my mechanic about this who is a BMW guy), the currently control arm selection, including Lemforder, is not made to the quality that they used to be. I just bought a full front set of Lemforder for the 540i, and they did not come with the BMW logo ground off like they used to. Something has changed in the parts supply chain in the last 5 years or so, where I'm strongly thinking of returning these and putting up the difference in cost to FCP to upgrade from just regular Lemforder to the genuine BMW arms. I'm surely going to return the arms that are bad on my E38 and going with Genuine BMW. I don't know who is making it for them now, but they must be a higher quality than the crap we are buying now. So mad.

Frankie, I know you've been dealing with this for a while, and I can't speak to your situation. But for the rest of you, if you are experiencing excessive wear, cupping, or chunking, you have a suspension or alignment problem! I am getting more than 10k on the tires on the 540 sport easily. I will check tonight when the wife gets home and post the mileage. I know its more than 10k, because we fixed her transmission seal 10k miles ago and these tires were on before that. On there now are Firestone Firehawk Indy 500 tires -- a performance summer tire.

I don't have my E38 right now, but that car had used all-season Contis on there with boat loads of tread left before I replaced them needlessly with Firehawk Indy 500s as explained above. I had a ton of miles on those and my suspension is lowered with Bilsteins and aligned to sport suspension specs. I'm just going by my cars guys.

Keep an open mind, because the issue can be bad struts in the case of cupping and chunking, bad control arms in the case of odd wear, shimmies and noise over bumps, or a worn out steering box in the case of shimmies, noise going over bumps, and vague steering. I've been chasing the noise over bumps and vague steering for years, and feels good to have the confirmation from the shop that it's the box.

Just to reiterate again: the wear and chunking in post #1 and #2 in this thread from 3 years ago IS NOT NORMAL. You should not be cupping or chunking your tires unless the tire is defective.

[rslifkin]

Frankie, what do you run for alignment specs? And how hard do you tend to drive the car? Also, what kind of wear do you typically see on the tires? That all might help narrow down a way to improve the situation.

[Frankie]

Frankie, what do you run for alignment specs?...

I run front K-Mac camber plates "in spec", adjusted towards the mild (least aggressive) end of the spectrum coupled with swiveling Rogue Engineering front thrust arm bushings. Tread wear has not changed at all. Symptoms are the usual: front outer tread wear and inner rear, with disappearing tread depth overall...the same as everybody else. It's all in this thread.

I do not drive my car "hard". It's a daily driver for work, all highway miles.

When I said excessive tire wear was a fact of life on the E38, I'm not kidding. Get used to it folks, especially with Sport models. Supporting sources include none other than Mike Miller from Roundel magazine's Tech Talk column. In my communication with him, he also suggested running slightly out-of-spec alignments, but don't expect too much. Two highly credentialed indy mechanics in my area concur.

Of course "excessive tire wear" in this context does not include cupping or chunking, but instead the type of wear jimmythefish and I are experiencing. That's the price we pay for the handling qualities BMW wants for its heaviest cars.

[racer2086]

Ok I said I would look up the miles on the tires on the 540 and report back. I'd look up the E38, but that is still at my parents place after the transmission work.

The 540i is a true sport with full sport suspension. All of the front suspension is original at 123k miles and needs some attention for creaking. The rear got new guide rods in 2014 and also new ball joints by me after BMW said they could not get the rear camber aligned properly.

Current tires now are Firestone Firehawk Indy 500, stock sport size aired up to recommended pressure.

Rears were installed at 101k miles and fronts were installed at 104k miles. So the rears currently have 22k miles on them and the fronts have 19k.

I quickly felt the front and they were not to the wear bars. Too much going on this weekend, so I have not yet pulled out my tread depth gauge to measure, but can do that and report back maybe with some pictures next.

Are the front outsides wearing? Yes some, but they are not feathered, chunked, or cupped like some pictures I see on this forum.

So, I wouldn't blame sport suspension for worn tires. I'd probably blame the tires. I had Conti DWS on there before while we were up in CT. By the time we moved back down to FL, the inner of those on the rear were wiped. But to be fair, they had good miles on them and we each drove down CT to FL with our cars literally FULL of stuff. Easily an extra 800-1000 lbs if not more (you could feel the obvious increased stopping distance). So I'm not surprised the rear wore like that.