My truck has been producing some strange tire wear on the the inside edges of the front tires. It is not typical toe-in wear camber wear. It is a cupping type wear that shows up on the inside 1.5" of the tread. I am running BFG AT/KO 235/85r16 at 80 psi on factory wheels. On the inside edge, one lug will be normal height and the next will be 3/32 or so shorter than the rest of the tire and alternates every-other lug all the way around the circumference of the tire. Wear is visibly noticeable after about 5k miles.
I am a bit stumped. Ball joints are good, they are tight and were replaced 39K ago. Steering linkage is tight and in good condition, and the steering box is properly adjusted. My shocks are factory originals, well due for replacement now after 128k miles.
That can be typical toe out wear on a bfg. because the lugs are so square adjacent tread lugs wear differently, instead of feathering. I've seen it before on open block/shoulder tires. Is it the same on both sides?
Any inside wear indicates alignment trouble. Have it realigned by a reputable company experienced with larger vehicles. I'm curious as to why you are running 80 lbs in the front. I only run 55 on mine and have not had any problems.
The bearings are a good idea too, somehow assumed they were checked. Loose bearings can cause the wheel to wobble around. Unlike bad ball joints which would have a similar effect of allowing the tire to tilt in at the top, when brakes are applied the forces work differently on the tire which can cause some odd wear patterns if bad enough.
I'll have the truck on the lift tomorrow to fix stuck caliper slides on the driver side front, so I'll check the bearings and double check everything else for play while I'm at it. If all is good, the truck will be off to the dealer for an alignment.... I sure do miss having the use of a brand new Hunter rack.
I run 80 psi all the way around because the truck gets loaded up on a very regular basis, and this time of year it has 160# of winch and mount hanging on the front too. The tires run flat against the road and don't wear any extra, I get a little better mileage, and I also don't mind a firm ride.
I'm trying to make up my mind on doing a small lift before I buy shocks, I should probably make it up soon.
I am having the same problem on my 2003 F350 LE super duty 4x4. This is the third set of front tires that have worn on both the inside and the outside. The center of the tires are almost like new when the inside and outside are nearly worn through.
I run 90 PSI in them or they look half flat. I think it is the weight of the diesel engine that puts so much weight on them. I tried 50 lbs an went through a set of tires in 7,000 miles. With 90 PSI I get about 12K.
The wear starts with evey other lug both inside and outside and only about 1.5 inches in. Then within about 10,000 miles the tires are gone. I have had it aligned twice with no help from it. I am now looking at replacing most of the front end joints.
I had similar cupping and wear like you mentioned. When my alignment guy looked at it
he replaced that bushing on top on the left side and cross rotated the tires. He said to
drive it a hundred or so miles and the noise should go away. It did! Mine came with Cooper
off road tires and will be getting replaced before long with something for the highway.