[apcnc]

What gear ratio do you have? That has to be part of it but it sounds like you may have another issue also. The truck should have plenty of power to pull that. Mine is an 11 (3.42:1 6L80) also and I have no issue maintaining 70 or more with that weight.

 

[apcnc]

That's strange because its the complete opposite of that to me. F**D has come along in the last 4-5 years but before that especially with the 5.0 there was just no power there. And a 4.6 just had no business in a truck. Every F**D I have driven just cannot deliver with the gas engines. With that said on paper the new ones look decent but I haven't driven to see for myself.

You and I have basically the same setup and the vehicle your comparing to cannot begin to compare with mine. So this puzzles me. And not holding 60 MPH? Is a very long very steep grade? You have a problem somewhere. I would straighten that out before making the mods. How many miles on the vehicle? Does it run and idle ok without a load?