Good news. It is optimal to run identical tires on each corner, but in reality they aren't identical very long anyway. I agree with Cristo's statements.

I'm curious: Did they ever tell you how 16" non-flats got onto the car?

 

In post #34, OP found out he actually had non-RFT on his mini..

 

Yes, I know that. I'm asking if the dealer ever told him who put 16" non-runflats on his car and why.

 

Yes. The GM told me, "Some base models with upgraded rims come with run-flats while others don't." He continued, "This is because base models have room for a spare, where the MCS models do not." How could I argue with that?

They're refunding me "around $700" but "probably" going to the finance company (in my case, BMW of North America Finance). Not sure what happens with that money then. I've been paying 1.9% interest on my entire loan for a year now, never late once.

Lesson learned. :(

At least I don't have to deal with run-flats. Besides, I have my entire immediate family on AAA Gold for years now.

Regards,
David

Sent from my iPhone using NAMotoring

 

Don't worry about having slightly more tread on the new tire as compared to the other 3 tires. The rule of thumb I've heard from tire places is that as long they're within 3 percent you're okay. I don't remember if it's 3% diameter or circumference though; probably circumference. I believe the 3% concern has to do with the car's ability to make accurate calculations for the ABS and DSC systems.

Remember that a new tire has an oily release agent/film on it so it will take several hundred miles to wear off and in the meantime the tire will be more likely to slide in corners and will feel kind of funny as it responds slowly to steering inputs, even if the new tire is on the back of the car. This will be much more noticeable if you have 2 new tires rather than just 1.

With a deeper tread the tire tread will squirm a little more so will respond to directional inputs of the steering wheel a little slower. Having a deeper tread is kind of like having a softer tire. This is probably what you're concerned with. In your case I don't think this will be very noticeable because your old tires still have quite a bit of tread left on them.

To prevent the back of the car from sliding (oversteer) due to hydroplaning in wet conditions, the deepest treaded tires should be installed on the back. During the dry seasons I would put the deepest treaded tires on the front because the fronts wear faster.

Here's a Tire Rack article on this topic. Unfortunately it's not very helpful:
Dangers of Mixing Tire Tread Depths

 

No point in arguing with the GM. You can escalate via email at MINIUSA.COM or by calling them at 866-275-6464 to ask why you paid for the more expensive runflats by default when you bought the car and what they are going to do with your refund on the tire warranty. Or call it a day and move on.

 

I agree that you should not have any problems with getting only 1 new tire and having it moved to the rear.

Once I had my front tires on another car rotated left to right and that seemed to cause a pull to one side.

From your photos, your tire tread depth looks fine.