Avoid any American vehicle with a V6 engine, especially oness from Ford.

The Chevy/GM 4.3 liter is actually quite good in the right vehicle but that is not a pickup. It is 3/4 of the ubiqitous Chevy 350, sharing the same pistons, et al.

Your best bet is the full-sized Chevy/GMG 3/4 or 1 ton with a 350 cid small block. They were discontinued in 2004 (I believe that was a 2005 model year). Get a good low-milage truck with the features you like (auto trans, one might suspect) and keep it maintained. Should last a lifetime.