hogbus, If you will look at engine horsepower stats they all increase in power the faster they rev to a point then they drop off. At 65 mph you should have more power than at 45. What cam was used when it was rebuilt?

We would need more input to help you further. I would guess that you have a fairly low rear ratio like my truck does, there for you won't feel the punch as good with a higher ratio. I'm using terms backwards.

I can tell that my truck has more power @ 3800 rpms but it's also above 75 mph.

I don't pay any attention to GVWR, it is totally meaningless in real time. I have hauled 5500lbs in the bed of my truck, I have pulled 6500lbs+- with it. If you paid attention to that you couldn't haul anything. IMHO



John