M3P Tire Wear & Alignment Questions

[mjolley9]

Hi Folks....Looking for some insight on my tire wear on my M3P (and alignment)

Car is approx 7 months old with ~4800 miles, and the stock Pirelli's are completely shot in the rear (3/32 on outside, and approx 1/32 towards the interior) on both driver and passenger side. Front tires are both at approx 8/32nds.

I always ran MPS4's on my prior BMW M5 (and generally got 13k miles out of the rears on it, which was driven much harder than my tesla), so I changed out the rears on the M3P to Michelin as well.

Once I got the new tires installed, next stop was alignment. Several shops refused to touch a tesla (which is beyond odd...but ok), so I went to a local "Mr. Tire" in my area that had good reviews online and agreed to do the alignment. When they took the car to the back, it took all of about 25-30 mins to complete and then they called me up to check out. At which point, I asked for the alignment sheet and they said the printer was broken.....so I said email it to me, which they couldnt do....so then I asked to speak to the tech.

The tech tells me the alignment wasn't all that bad to begin with, and all that was adjusted is the front toe. I asked how could that be given the front tires are wearing evenly, yet my rears not so much (and wearing excessively fast), and they said the front toe adjustment should fix my issues.

I don't know enough about alignments to completely call BS, but I get the sense they pulled my car into the bay and didn't do a thing. Can a slight fix on the front toe fix rear tire wear? And for how fast it ate a pair of tires, should I instead be concerned that the rear suspension/ball joints/etc has an issue? When I initially had trouble finding a shop to do the alignment, I almost just paid Tesla their outrageous $275 fee for it, but the first appointment is a month away.....

Thanks in advance

 

[Gauss Guzzler]

Alignment shops usually offer two tiers of service:

• Basic alignment for American cars which includes front toe only
• Deluxe 4-wheel alignment for European cars (Tesla, Rivian, Corvette, etc.) which includes everything, but they only adjust the front toe

The reason they only adjust front toe is because it's less work than adjusting all 4 wheels. And since the wheels are all measured relative to each other, changing the front toe gives the customer the illusion of a 4-wheel alignment as the numbers for all 4 wheels will slightly change.

I suggest that you return and remind them that you had tire wear and would like to have the rear axle aligned as well. Your intuition is correct that the wear was extremely abnormal and that they did nothing to correct it. There's not much to go wrong with the rear suspension so it's likely just misaligned for some reason.

 

[mjolley9]

Alignment shops usually offer two tiers of service:

• Basic alignment for American cars which includes front toe only
• Deluxe 4-wheel alignment for European cars (Tesla, Rivian, Corvette, etc.) which includes everything, but they only adjust the front toe

The reason they only adjust front toe is because it's less work than adjusting all 4 wheels. And since the wheels are all measured relative to each other, changing the front toe gives the customer the illusion of a 4-wheel alignment as the numbers for all 4 wheels will slightly change.

I suggest that you return and remind them that you had tire wear and would like to have the rear axle aligned as well. Your intuition is correct that the wear was extremely abnormal and that they did nothing to correct it. There's not much to go wrong with the rear suspension so it's likely just misaligned for some reason.

Thanks - your reply was quite helpful, and confirms my suspicions. Funny thing is I told them upfront about the rear tire wear and why I was getting the alignment. After they couldn’t produce the alignment sheet, didn’t give a satisfactory answer on alignment, and my steering wheel is now crooked….i decided to take it somewhere else.

A highly reputable shop in my area (that I’ve used before, but is a good deal more expensive) confirmed that not only was my rear toe way off, but even my front was out of alignment. It seems the local “Mr. Tire” actually made my alignment worse on the front, and did nothing on the rear.

 

[Gauss Guzzler]

Glad you got it sorted. Now that you actually have a printout, consider showing it to the first place and requesting a refund.

 

[canasion35]

I stand with the alignment tech to give them specific values to hit. Only adjusting toe up front isn’t going to solve the rear issues.

What’s your printout now show? The rear toe was probably out before so it’ll be interesting to see what it was, and what it is now after you got it aligned.

 

[mjolley9]

Glad you got it sorted. Now that you actually have a printout, consider showing it to the first place and requesting a refund.

Oh yea...I stopped there on my way home. They refused to provide a refund, claimed the alignment was completed and not refundable.....refused to even look at the alignment sheet and just argued with me. Lesson learned, never go to "Mr. Tire" and I'll just get my money back from Amex.

 

[mjolley9]

I stand with the alignment tech to give them specific values to hit. Only adjusting toe up front isn’t going to solve the rear issues.

What’s your printout now show? The rear toe was probably out before so it’ll be interesting to see what it was, and what it is now after you got it aligned.

Yep - Rear toe was showing 0.50 and 0.66 for a total toe of 1.16. Afterward, it was adjusted to 0.17 and 0.18 for a total of 0.35. I'm assuming that's now in spec (albeit would probably be better from a wear perspective to be closer to zero).

While my initial inclination would have been that "Mr. Tire" just rolled the vehicle into the shop and did nothing, I do know they made a change to the front as my steering wheel was off center when I pulled out of the parking lot....Those guys were clowns.

 

[Mariano]

I have uneven tire wear and was told it is pretty standard for the M3 due to the weight of the car and the instant torque.

I was also told there aren't many things I can do about it other than purchasing an aftermarket camber and toe arms for the vehicle in the rear.

Here are photos of my front tires

Mariano

 

[Gauss Guzzler]

That's definitely uneven wear but whoever told you about it being standard doesn't know anything whatsoever about cars, weight, torque, or tires.

It looks to me like your front toe is out of spec. Nothing aftermarket is needed unless you have lowered the car a lot.