prorate the tire across from the damaged one. The other driver admitted 100% fault. My mechanics and other tire places I called strongly suggest that all four tires should be replaced because if not, it will eventually cause differential and/or transmission problems over a period of time. I read online that the sensor for the AWD will be confused and will not perform to it's full potential. I have to replace all the tires because my current tire model is no longer available even though Ive been told that they still have a lot of life left on them. (9/32). I do not want to come out ahead but I also can't afford to pay out of pocket for new tires. I just want to be made whole. Also, the insurance co. will not reimburse me fully (only prorate) for the two child car seats.
You should consult with a local atty. Maybe a letter from atty will get them on track. If your ins co will do what you want, have them do so, and let them go after the other side. You may have to take a shot in small claims court.
Regarding the tires, it's true that the shops recommend changing all four tires because of the differential issue. You can argue that it's not safe to change just one tire and they are responsible for all four but it will take some convincing and probably a lawsuit.
The child seats will depreciate in value over time so I think the insurance company is right on that issue.
The company only has to replace the item at it's market value, not replacement value. So get statements from mechanics, and others that the "repair" of the tire means replacing all--in other words reframe it as a repair job and this is what it takes. Maybe get the dealer to give you a statement, copy anything in the owners manual or ask for copies of any service manual the dealer shops get.
If they don't give you the value of the tires, replace them but save the tires that are good if you need a replacement in the future.
However, one site said that the "gotta replace all of them" is not true for all cars. See:
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