My 740 will not wear tires evenly. I have put 5 sets of tires on. Some summer tires, some winter tires, some "all" season tires. I have 16 inch turbo wheels and 15" steel winter wheels. There is consistent outer edge cupping on the fronts. I have complained to my front end shop over and over. They are about to loose me as a customer. My suspension is almost all new IPD. Top and bottum Cherry Turbo braces, bilstein shocks, poly bushings on the strut rod and on the IPD roll bar. I have had the towers apart and replaced the upper bearing on one side. The ball joints were replaced. Still tire wear. The shop has tried neutral settings on the toe in and some variations of toe in. They all seem to drive fine, but have not stopped the wear. I drive about 1200 miles per week. It is mostly highway driving, but I do get onto dirt roads and nasty country roads every week. The car has 201K. I bought it with 130K and the tire wear seemed to start last summer with the Korean tires. The wear started with all the front end work I did. Ooops!
I rotate only every 10,000 miles. I do this on all my Volvos. (we are down to 4 all rear wheel drive). This is the only one with wear issues. I have not asked anyone for help with this before. I wonder if there is some special toe in setting I am not aware of. The Camber is not adjustable without filing out the bolt holes. One of my towers had been slotted out by the factory or someone after it was built. When I installed the upper cross brace, the tower was pulled back into its original position not using the slots which tipped the tower out. My front end shop tells me the camber is in specs. I have had 4 tire sizes on. Two of them were plus sizes. The tires were a set of 225 16 no names which were on the car when I bought it. They seem to have worn evenly. My first notice of high wear was the 205/50ZR16 Kumho Supras. They wore fast. Great grip, ugly driving. They would rip the wheel out of your hands if there was a crack or crevis in the road for them to follow. What a trip they were. They did look fast and etc. Then I had Blizzaks, then 205/55HR16 Bridgestone Tur H Revo's. They cupped fast also. I am back on Blizzaks for winter and they are feathering also. Outer edge front only. Both sides.
I think the more parts I put on the front, the worse my wear has been. I notice that the ball joints could be reversed into their mounting hole. The bolts will go in with the offset of the ball joint either way. There is a chance I have them in backwards which might explain the problem. However, the front end shop says the front end is in specifications. They hand me a stupid printout showing all the settings. I live in a small town near Chicago in Indiana. There are not many shops to choose from. Only a nut like me drives Volvos in this area. Trucks with high lift kits and dual rear wheels seem to be the sports car of choice around here. I am tempted to show some of this wear to the guys at Tire Rack.Com where I buy tires. I am fortunate to be able to drive into there place and purchase tires. They do a good job with high performance tires.
I would appreciate hearing from you. Perhaps you have had the same experience with a 740 wagon. Thanks.