just brought my 05 cc swb v10 4x4 in for warranty work. problem was it has too much steering oscillation going over bumps. they tightened the steering lash and it seems to have cured my problem but the steering is much harder but i can live with it tech said it will free up with use. also had to replace both f250 emblems. truck would lean 1 inch lower on left rear. tech put in a 1/2 in shim between leaf spring and block. now it sits only 1/4 inch lower on left much better than before. looks level dont ask how 1/2 shim made it only 1/4 less but that is the measurement. all this was performed under warranty

 

If the other side does not have the same shim...then I would take it back and not except the cure?. For a NEW truck...I don't think so! They should replace the rear sagging spring...IMHO. Both would be preferred of course.

If it did not come from the factory that way...then do not except the shim as a fix. Think about when it comes time to trade-in or sell. What you going to tell the potential buyer? Plus...as you put more miles on the truck...it might get worse.

Good luck...

biz