[QUOTE=bigtexan99;9325119]My mechanic looked at the tires today and said that type of wear is caused by bad shocks, not alignment.


I don't know about that, I don't see much cupping on your tires. It could certainly be a combination of alignment and shocks, but I'm thinking you should try to get an alignment also.

 

It may not show in the photo, but it certainly looks like cupping in person.

 

If it is "just cupping" then by the looks of your photo it is all on the inside of the tire tand that means you have EXCESIVE amount of negative camber. I Forgot what the f series 4x4 is but the E series is usually only -0.60 and that looks like you are at -1.5 or worse. and that ussually means you have really bad ball joints. Usually the 4x4's have a camber closer to 0 than others.
From the looks of thoes photos I am ready to bet that your toe is too far negative. Normally on the vans it is total toe: +0.06 or +0.03 per side. I am guessing you are at total toe -1.00 or around there.

 

But don't you think it would be odd for ball joints on both sides to fail at the same time? Same goes for shocks. While shocks can produce that exact wear pattern (been there done that when a brand new shock went bad), sagging front springs will also cause that same type of wear. The difference is sagging springs create the wear equally on both tires, since both springs tend to wear out at the same rate. The link I gave earlier had pictures on what to look for and how to measure to check it.

But I still think he needs 4 new shocks too.