i'm in the same boat as you are. mine is coming from the front and has recently started at 38k. Suspension [wheels] wise i have 17/235 and i also went across a ditch and spun around 4 times at 34k, that's what i thought induced the crunchy sound. But now that you say something I'll stop by the dealer for a routine fix here and there....I've been there so many times by now I might as well take them out to dinner I guess....sh** since i had my 3 i put more miles on rentals then my baby. But back to topic, I'll let you know what the stealership's diagnosis is.