I know this has been gone over before, because I searched. I'm interested in some more indepth details about this situation.

I know that mis-matched sizes front to rear and side to side can cause damage to the diffs. Even tire wear can cause damage. I've even read in the owner's manual they suggest keeping all tires the same brand, size, wear, etc.

Now, I just installed my all-season tires for winter use and noticed my tread depths. It made me worry. My tread depths are roughly 5-6/32" maybe 7 in the front and 3/32" (not an optimal depth for snow, but that's beside the point) in the rear. Before I bought my Dunlop Z1's, I used my all-season's at these tread depths for about 6 months (probably more like 6-7/32" front and 4/32" rear back then). No issues. I bought the car used, certified from a Honda dealership in that condition.

I don't daily drive my car, not even in the summer. So during the winter, my Evo will be used even less, maybe once, POSSIBLY twice a week. But I wanted to switch over to my all-season's just incase I have it out and get stuck in snow, or just want to have fun in the snow

Are these tread depth differences anything to worry about? Am I being paranoid? I tend to be overly paranoid about these kinds of things. Keep in mind the car will only be using these tires for the next 4 months, tops. Not to mention I change my drivetrain fluids every 10k. I read on Tire Rack different car makers have different tolerances to tire wear. I'm not sure where Mitsubishi stands other than what the owner's manual says. It'd be damn near impossible to keep the tread depths perfectly even. I'd imagine a few 32's are ok.

Any help or advice is appriciated

 

Anybody?

 

Talking about 2mm difference. I think you are ok. I have wear like that on my Z1* from AXing.

 

If you have a major difference in tread depth you could have a difference in circumference and that’s what really matters to the AWD. Pick up a cloth measuring tape, usually fabric stores have them, and start by checking the circumference at the center of the tires. I normally do this while rotating the tires, set them in the sun to warm up, be sure your cold pressure is correct to start with.

 

its fine. with that minimal difference, the center diff wont be working too hard so the viscous coupling unit wont overheat.