I recall reading that with a full time AWD vehicle, it's important to have equal tread depths front and rear. Does anyone know what the allowable tolerance is? Looking at various sets of low mileage used winter tires for sale locally that I will be checking with my depth gauge.

 

Tire Rack claims it should be within 2/32nds front/rear. However Acura claims that's for "traditional" AWD and SH-AWD isn't really impacted.

 

If anything, just find a set that are pretty even.

 

i bought a used tire with more tread than the other three i had already on the car and now giving it the beans, the car tracks towards the newer tire. to the right.

that's all thats going to happen, your car might track differently.

do some burn outs to equal out the tread

 

SH-AWD + burnout =















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Yeah it all worked out as the set of snows I picked up were barely even used, 9/32nds all around. The car drives better on these than it did with the OEM Michelin allseasons, which still had lots of tread and were all even, but I think time has made them squishy, the car would sort of tramline or get squirrely a bit for a second or two after lane changes at highway speeds, which has been getting worse in the couple of months with everything checking out fine with the suspension, etc...so it's going to be new all-season or summer rubber in the spring.

 

Which Michelin All-Seasons do you have? The Pilot HX MXM4's that the RL comes with are questionable at best....

 

That's them. Appears to be the same set the car came with when new (I'm the second owner of the car, just picked it up about 2 months ago). After they were off the rims, the sidewalls are noticeably "weaker" and flabby just when picking them up than the sidewalls on two different sets of winters I had in my garage (one being the "new" set of used 18 inch Michelin X-Ice that went on the car replacing the all seasons, and the other was a set of 17 inch discount brand winters I had on my old 06 RL). There also looks to be some fine cracks starting in the sidewall rubber, so I'm definitely getting some new rubber in the spring.

 

Even with my and Heavy's insistence on avoiding staggered setups through the years, plenty of people have done it. We don't have any scientific evidence behind it, but the concensus here (or at least in my mind) is that if you can size the tires to within 1%, or just over 1/8", front to back, you should have no worries. Biggest concern with a difference is overheating the transfer case. You and I both know that plenty of these people couldn't or didn't get their setup to with 1%, and we have never heard of a drivetrain failure on a staggered RL here.

The biggest focus with concern to safety is matching adjacent tires.