it's a v6 short bed. When I brake fairly hard, the back end feels like I am going across a washboard road. Light braking may only produce a few bounces. My first thought was brakes, but they have been rebuilt. When I rebuilt them, I thought the rear axle bearings felt a little "dry", but I could never decide if the roughness was the axle bearings or the differential. Anyway, I am wondering if anyone has encountered this before, and if there are ways to diagnose it without just swapping parts. Just bouncing the shocks tests out OK. So I can't figure out if it is the shocks, leaf springs, or possibly some kind of drag in the axle.
Thanks, Roscoe