If you have any emblems/stickers that you once had on the body of the truck and that are now peeling off leaving behind that glue residue, here is a great way to take it off:

Take car wax polish and apply it to the surface. Let it sit for about 10mins and then start wiping with a rag and the glue will melt right off as though you had used paint thinner .....

I did this with MOTHER'S CARANUBA wax polish .... very remarkable results....

Milspec

I use a product called Goo Gone. You will find this in most paint sections. No harmfull chemical and has an oily texture. I use it on all stickers and even my hands sometimes. Plus it has a lemon scent to it.

SELWA

My old method was a Hair dryer, Goo Gone, and disposable plastic drywall knife before I got one of these, a 3M pinstriping removal tool:

actionpaintball

I've removed a lot of vinyl signage with the 3M pinstriping removal tool. It is a rubber-like wheel that attaches to a drill. It will take them off easily. Then just clean up any left over residue with the products mentioned here. You can get the 3M pinstriping removal tool at most automotive paint stores.

Keith