This is similar to running at low rpm's at too high a gear. The truck lurches until you downshift. It doesn't do it on acceleration or pulling a load, just coasting at 30 to 45 MPH. The lurch is very mild. I have changed fuel twice to different brands and that doesn't make a difference. This happens on full or low tank. Replaced fuel filter with no change. Wondering if this is an injector problem?