[w0bbles]

Hi all. I’ve been having issues with fast, uneven tire wear a lot. I am getting ready to purchase my 3rd set of rear tires in a little over a year. I posted my alignment spec and at 0.19 positive toe, people were saying that’s somewhat normal.
So what I’ve noticed recently is that my rear end feels really loose at medium to high speed. If I hit a crack or bump on the road, the whole car jerks to that side, almost feels unsafe. It was worse in the rain, to the point I couldn’t go past 50mph without feeling like I was going to run off the road, but I thought that could be because of bald tires.
What could cause this? Worn out bushings? Worn out shocks? I’m wondering if whatever the issue is, it’s also causing my rapid tire wear?

The car is a 2013 335i M Sport with all stock suspension and 20mm wheel spacers

Thanks!

[cruizinmax]

Do you have a pic of the alignment sheet? Also do you know if it was adjusted with weights loaded in the car or not? Are the tires wearing evenly across the tread, just fast, or wearing the inside tread?

[SnapCoupe]

Originally Posted by w0bbles

Hi all. I’ve been having issues with fast, uneven tire wear a lot. I am getting ready to purchase my 3rd set of rear tires in a little over a year. I posted my alignment spec and at 0.19 positive toe, people were saying that’s somewhat normal.
So what I’ve noticed recently is that my rear end feels really loose at medium to high speed. If I hit a crack or bump on the road, the whole car jerks to that side, almost feels unsafe. It was worse in the rain, to the point I couldn’t go past 50mph without feeling like I was going to run off the road, but I thought that could be because of bald tires.
What could cause this? Worn out bushings? Worn out shocks? I’m wondering if whatever the issue is, it’s also causing my rapid tire wear?

The car is a 2013 335i M Sport with all stock suspension and 20mm wheel spacers

Thanks!

The rear end of these cars typically feel pretty loosey-goosey with stock suspension. Going over the crest of a road while overtaking on throttle will make the rear end wiggle quite a bit in an unsettling fashion. This gets worse/more noticeable with higher mileage or if you have a tune (extra torque).

That being said...

Unless you like to slide or do burn outs every time you get an opportunity, 3 sets of rear tires in a year is NOT normal. To help you out a bit more we are going to need some more info. How many miles are on the car? Have you had the spacers on for the past year as well? Have you hit a curb or gotten in an accident where the rear end of the car was the focus?

Your toe numbers are pretty normal, but that doesn't tell the whole story. There could be something loose or broken that only causes issues at speed, not when the car is stationary on the alignment rack.

[w0bbles]

Originally Posted by cruizinmax

Do you have a pic of the alignment sheet? Also do you know if it was adjusted with weights loaded in the car or not? Are the tires wearing evenly across the tread, just fast, or wearing the inside tread?

Here’s the specs from November. Don’t mind the date on the sheet, guess the machine wasn’t set.



Here’s the wear from when I bought the car in April of last year till right before new tires and alignment in November.








And here’s the wear currently. These tires were purchased in May, after the set I had purchased in November went through the same wear.

[w0bbles]

Originally Posted by SnapCoupe

The rear end of these cars typically feel pretty loosey-goosey with stock suspension. Going over the crest of a road while overtaking on throttle will make the rear end wiggle quite a bit in an unsettling fashion. This gets worse/more noticeable with higher mileage or if you have a tune (extra torque).

That being said...

Unless you like to slide or do burn outs every time you get an opportunity, 3 sets of rear tires in a year is NOT normal. To help you out a bit more we are going to need some more info. How many miles are on the car? Have you had the spacers on for the past year as well? Have you hit a curb or gotten in an accident where the rear end of the car was the focus?

Your toe numbers are pretty normal, but that doesn't tell the whole story. There could be something loose or broken that only causes issues at speed, not when the car is stationary on the alignment rack.

I see. I didn’t tinker with the toe a bit yesterday and for some reason the rear end feels looser.

I do not do any sliding or burnouts. Occasional getting on it momentarily but that’s about it. Mostly commuting.

The car has 84k miles. I bought it with 63k back in April 2017. Spacers have been on since November. I don’t remember if it was before or after the alignment. I think after.

I hear mixed thoughts about this kind of toe. And you could be right about something broken. I was wondering if blown shocks could cause all of this and if I should look into a set of coilovers.

[Biginboca]

Your rear camber and toe are both out of spec, so why not start with the obvious and get those fixed?

Bad suspension bushings, bent control arms, blown shocks, and the too soft rear subframe bushings these cars come with can all contribute to the loose feeling rear end. But I would start with getting the alignment correct.

If your toe can’t get into spec then you likely have a bent control arm. If it will I would then start checking bushings and address the rear subframe bushings with inserts or replacements.

[Donutz]

I would take the wheel off and see if there's anything rubbing the tire. I've seen similar damage at the track with contact on the fender, inner liner or suspension components. Not to say it isn't alignment related, but I'd still look for shaved rubber / contact marks in the wheel well.

[w0bbles]

Thanks guys!

Quick update, I put the toe back to where it was and the jerkiness disappeared. So that was definitely toe related.

As far as the other possibilities, it makes it hard to pin it on bent arms or anything since the issue resides on both sides. I’ll start with getting the alignment done again with less positive toe and go from there.

[byebyev8]

Thats an alignment issue no question. My car was like that when i first got it at 50k 5 years ago. I put on a diff brace and it helped a little. Finally an alignment fixed the issue.

[w0bbles]

Originally Posted by byebyev8

Thats an alignment issue no question. My car was like that when i first got it at 50k 5 years ago. I put on a diff brace and it helped a little. Finally an alignment fixed the issue.

Can I ask what you set your toe to?

[feuer]

Originally Posted by w0bbles

Can I ask what you set your toe to?

Definitely toe. Definitely not tune as someone above suggested lol ! Try 0.05 for even tire wear. Starionary 0.20 becomes 0.25 maybe 0.30 rolling forward depending on how worn the suspension components are. Diff lockdown dies help too. I recommend VWETISH on n54tech. At 85k you should look into getting new struts and shocks. However they won't help with this type of tire wear.

[chatch10]

Check your rear toe arms. Mine were shot, but you couldn't tell because the bushing was binding inside the arm. You could align it, but there were still issues when I would hit a bump.

[w0bbles]

Originally Posted by feuer

Definitely toe. Definitely not tune as someone above suggested lol ! Try 0.05 for even tire wear. Starionary 0.20 becomes 0.25 maybe 0.30 rolling forward depending on how worn the suspension components are. Diff lockdown dies help too. I recommend VWETISH on n54tech. At 85k you should look into getting new struts and shocks. However they won't help with this type of tire wear.

Got it! Thank you! I’ll set it to 0.05 and go from there.

What is a diff lockdown?

[w0bbles]

Originally Posted by chatch10

Check your rear toe arms. Mine were shot, but you couldn't tell because the bushing was binding inside the arm. You could align it, but there were still issues when I would hit a bump.

Was this for the tire wear or the jerkiness?

[chatch10]

Originally Posted by w0bbles

Was this for the tire wear or the jerkiness?

Jerkiness. Whenever I would hit a bump I would hear a creak and get a wiggle from the rear end. That went away instantly with the new rear toe arms and an alignment.

[w0bbles]

Originally Posted by chatch10

Jerkiness. Whenever I would hit a bump I would hear a creak and get a wiggle from the rear end. That went away instantly with the new rear toe arms and an alignment.

Ahh ok. Well mine ended up being the toe adjustment. I put it back to where it was (at 0.2) and the jerkiness went away. I think it has to be aligned with the front accordingly.

[feuer]

Originally Posted by w0bbles

Got it! Thank you! I’ll set it to 0.05 and go from there.

What is a diff lockdown?

It's aftermarket part that reinforces the differential. Read this: https://www.n54tech.com/forums/showthread.php?t=38313
Watch this:

[w0bbles]

New tires installed and new alignment done. Let’s see what happens now...

[w0bbles]

Originally Posted by feuer

It's aftermarket part that reinforces the differential. Read this:

Awsome, will do! Thanks!