Quick question. I did some research already and know that on some cars (Subaru's, Jeep's with Quadratrac) this is a problem, but if you have mismatched tires/tread with AWD, will it mess up the transfer case? My Dad has a 2000 Mountainer with AWD and was on a road trip this weekend only too find out there was a screw in the tire. The shop said they couldn't patch it so they replaced with a new tire the exact same model. So now there is one new tire and three tires with I'd say maybe 25% tread left. I suggested that he should at least get one more new tire so the axles are at the same speed. However I don't know how these tranfer cases work. Maybe they should replace all four, maybe it is fine, I don't know. Thats why I'm here for advice. Any info would be great before they tear something up. Thanks!