Tires: Feathering of front tires, target value, upper ball joints

Question
 I have a 2001 Mazda B-3000 "Dual Sport" truck. 6 months ago, the front tires were feathering, and the truck was pulling to the right. New upper ball joints, tires, and front alignment were done. The tires are feathering again, however. I plan on bringing it back to the repair shop, but could shocks be the problem? Someone mentioned a load kit, that it could need. It's not pulling right now, however. Just feathering the tires. It has just turned 100,000 miles, by the way. The truck doesn't bounce up and down, but I was told that the shocks could still be the problem. Any advice would be appreciated. Thanks.
                                           Earl Gros

Answer
Earl,

Did you replace the tires when did all this work?  

If not , then you may have fixed the source of the problem, but didn't fix the symptom.  After all, you can't put rubber back onto a tire.  The rubber will always be worn away and you can't get it back.

Another possibility:

My experience says that the published alignment tolerances are too wide.  Not the target value, but the allowable deviation from that value.  I think it ought to be half of what is published.

Put another way, the alignment should be within the inner half of the spec.

You should be aware that even vehicles that do not have a pull can be out of alignment.  There are settings where one out of spec condition is offset by another out of spec condition – typically camber vs toe.