[tac3331]

At 400 miles I had to replace rear right tire after road debri sliced the sidewall. Tire certificates from discount tire was my first purchase so was covered but 10k miles later realize a standard ps4s was used as the replacement as it had much less wear then all three other tires that were needing to be replaced. I do have awd and transfer box code cf5573. Discounts getting me the proper tires but discussing possible damage.

[Forzanerazzurri]

What's the question?

[Ximian]

Mixing a standard PS4S and the BMW star spec PS4S tire on the same axle is fine. You won't notice the difference. You also don't need to worry about the wear difference because a couple of mm in tread depth isn't going to damage anything.

[tac3331]

There's a difference between compound, tread design, weight and traction. Worried about those factors stressing my rear diff over those 10k miles.

[PLF69]

Originally Posted by tac3331

There's a difference between compound, tread design, weight and traction. Worried about those factors stressing my rear diff over those 10k miles.

I don't think you will have any problem having your diff warrantied by BMW (unless they come here to read this thread maybe). If you show up at the dealer with fresh tires, be it either star or regular and you have 4 of all the same kind they probably won't bother.

It may also be totally possible that your diff code has nothing to do with your tires, keep in mind these cars are built pretty strong to withstand track abuse, the stress on a full track day is worse that street driving for 9k miles with a different compound tire.

[tac3331]

If my car was all stock I'd just let bmw deal with it but they'd probably flag me for any issues or have to put it all back. Had the code before I modded it but figured the tire issue after.

[Skyscraper]

So you're trying to figure out if there is damage to your car from a slightly different tire?
No. You don't have a claim against the tire shop.

[tac3331]

Originally Posted by Skyscraper

So you're trying to figure out if there is damage to your car from a slightly different tire?
No. You don't have a claim against the tire shop.

Well even their own website states mixing tread patterns on an awd is a big no no. Why I'm asking for opinions.

[HawkeyeG80]

You went through tires in 10k miles?!

[tac3331]

Originally Posted by HawkeyeG80

You went through tires in 10k miles?!

3 out of 4. Why I'm questioning the effect of one not matching.

[Indo Rider]

Originally Posted by HawkeyeG80

You went through tires in 10k miles?!

Nothing out of the ordinary for a soft tire and someone who actually enjoys their car.

[Indo Rider]

OP, for what it's worth, I wouldn't be concerned about damage, or future warranty coverage at the dealership (assuming you show up with matching tires on each axel and don't offer all these details). But I think the uneven wear you experienced is good evidence to avoid mixing different tires on the same axle. Even star vs non-star... The best approach is always to have identical tires on an axel. I'd even say avoid significant difference in tread. It sucks when you have to replace a tire due to damage when the other side still has half tread remaining, but when you go through tires so quickly anyway, is it really that bad of a cost hit to just replace both? That's what I've typically done in the past, and then sell the used tire to get a few bucks.

[Mowe]

The star and non star size tire is different. I know because a non star 285 front did not fit but a star 285 (my previous rears) fit fine for what it’s worth.

I won’t give an opinion on whether it will be problematic for your diff. Don’t know enough.

[tac3331]

Originally Posted by Indo Rider

OP, for what it's worth, I wouldn't be concerned about damage, or future warranty coverage at the dealership (assuming you show up with matching tires on each axel and don't offer all these details). But I think the uneven wear you experienced is good evidence to avoid mixing different tires on the same axle. Even star vs non-star... The best approach is always to have identical tires on an axel. I'd even say avoid significant difference in tread. It sucks when you have to replace a tire due to damage when the other side still has half tread remaining, but when you go through tires so quickly anyway, is it really that bad of a cost hit to just replace both? That's what I've typically done in the past, and then sell the used tire to get a few bucks.

I had road hazard coverage from discount tire where at 400 miles they were suppose to replace with the oem tire. When my mechanic pointed this out and I brought to discounts attention they blamed michelin for bad info.

[tac3331]

Originally Posted by Mowe

The star and non star size tire is different. I know because a non star 285 front did not fit but a star 285 (my previous rears) fit fine for what it’s worth.

I won’t give an opinion on whether it will be problematic for your diff. Don’t know enough.

Could you elaborate on the fitment issues with the non stars?

[T0RM3NT]

Good information/video found here:

https://g80.bimmerpost.com/forums/sh...65&postcount=4

Credit to Limegrntaln

[tac3331]

Originally Posted by T0RM3NT

Good information/video found here:

https://g80.bimmerpost.com/forums/sh...65&postcount=4

Credit to Limegrntaln

I will clarify it wasn't my choice to mix tires. Discount tire did it thinking they were the same until I learned better.

[Mowe]

Originally Posted by tac3331

Could you elaborate on the fitment issues with the non stars?

It’s been stated and I found true that the tires may be the same number size, the reality is a star tire is a little smaller in overall diameter.

Star fit. Non star in same size rubbed up front.

[Indo Rider]

Originally Posted by tac3331

I had road hazard coverage from discount tire where at 400 miles they were suppose to replace with the oem tire. When my mechanic pointed this out and I brought to discounts attention they blamed michelin for bad info.

Yeah, I understand what happened to you and didn't mean to say you made any bad choice since you had no intention of mixing star and non-star. For the people saying it's fine to mix I was trying to point out that the difference in lifetime you experienced is pretty good evidence that mixing isn't a great idea. And if they are not exactly the same size to start with, that's even more reason not to mix.

[Dawgz]

Originally Posted by tac3331

At 400 miles I had to replace rear right tire after road debri sliced the sidewall. Tire certificates from discount tire was my first purchase so was covered but 10k miles later realize a standard ps4s was used as the replacement as it had much less wear then all three other tires that were needing to be replaced. I do have awd and transfer box code cf5573. Discounts getting me the proper tires but discussing possible damage.

Any updates on this?