My wife's 850 suffers from the same type of tire wear, I think the passenger front is more pronounced. When I bought the tlast set of tires, I inflated the pressure to 35 psi (max listed on tire sidewall). In less than 5000 miles the inside and outside edge of the front tires where almost down to the wear bars. The rear tires looked perfectly new, still had moulding nubs on the tread. I rotated the tires (front to rear) and inflated the fronts to 40 psi. The front tires (previously rear) were showing the same type of wear so I upped the pressure to 45 psi. I have managed to reduce the wear on the edges (it still seems to be faster than the center), but the center of the tread still looks relatively new.
Since these tires have been on the car I have replaced: shocks, upper strut bushings, ball joints (the car is a '93 model), sway-bar end links, tie-rod ends (alignment afterwards, but they didn't give me a report on the values). This is just speculation but it could be suspension parts that are worn creating the problem. I may have fixed my wear problem but I can not be sure since the tires were pretty messed up before I started making changes. What I can say is that I seem to have slowed the wear rate down with the various things I have done.
If you do solve the problem, please let everyone know.
|