So I have an 06 CCSB that is lifted and running 33's. They are the Bfg All Terrains... Between 65 and 75 I get a very audible hum and slight vibration throughout the truck while accelerating. If I'm coasting it isn't there, and sometimes it doesn't occur at all. It sounds like it is either in the rear or in the center underneath the truck. Where should I start looking to diagnose this problem? There are no vibrations in the pedals our steering wheel.
