[najnad]

Silly question: One of my tires got a nail in the shoulder of the tread and everyone says it is un-repairable as the safety of the tire is compromised. The remaining 3 tires have more than half of their usable tread depth left.

I cannot find the same tire as I have to match the others, so my plan is to buy 2 new tires and put them on the rear of the X3, leaving the old tires on the front. They will be the same size/aspect ratio as the old tires.

Anyone run two different brands/models of tires front/back? Any issues?

thank you

[oVeRdOsE.]

about in the 1% same wear, same outside diameter, same performance and yeah you'll be fine.

those are not F1, precisely tuned/balanced. even if you don't have the exact same tire specs, you won't die. x drive will be fine.
Its virtually impossible that all 4 tires are on the same surface , in the same time, with the same friction coefficient. Worst in rainy on winter condition; and the x3 do fine.

[Marty in NY]

Originally Posted by najnad

Silly question: One of my tires got a nail in the shoulder of the tread and everyone says it is un-repairable as the safety of the tire is compromised. The remaining 3 tires have more than half of their usable tread depth left.

I cannot find the same tire as I have to match the others, so my plan is to buy 2 new tires and put them on the rear of the X3, leaving the old tires on the front. They will be the same size/aspect ratio as the old tires.

Anyone run two different brands/models of tires front/back? Any issues?

thank you

Go here to be sure you are buying tires that are the same size as the two you are not replacing. --> https://tiresize.com/calculator/

As others have said, it should be ok if they are really the same size but may look strange since when looking at one side of the car, the fronts and backs may look different. Another option would be to buy four new tires and save your other ones in case you get another tire issue down the road.

[Opie55]

The issue is not different brands but different diameters due to wear. There is lot of info out there, and some car makers have actual recommended limits for differences in tire diameters in an all wheel drive system. A new tire has a tread depth of about 11/32". One half gone is 5 or 6. That changes the diameter such that the worn (smaller) tire rotates several more times per mile. That, at least theoretically, stresses the drive system. While there are a lot of warnings about it, I personally think it is very conservative advice because what I have never seen is people saying they had an actual failure attributable to it.

[najnad]

thanks everyone...I was more concerned with the potential differences in grip/friction from front to back causing issues with the X-drive software. Wasnt sure if anyone had encountered that problem or not as I didnt find anything similar when I searched this forum and online.

[Marty in NY]

Originally Posted by najnad

thanks everyone...I was more concerned with the potential differences in grip/friction from front to back causing issues with the X-drive software. Wasnt sure if anyone had encountered that problem or not as I didnt find anything similar when I searched this forum and online.

No need to worry about grip/friction, your wheel speed sensors will report that to your DSC and ABS systems which will counteract any issues. The only real potential issue is tire diameter. You can run a diff diameter if you run it on all four wheels, if you do that, your speedo will be off, either low or high but if you mix diff diameter tires on the car and are more than a percent or so off, that is not a good thing to do.
Like I mentioned before, if you intend to keep the car for say 30-40K more miles, I would buy four new tires of the same brand and size and use your current ones as spares.