04 3500 4X4 DRW crew cab with a CM bed and a 6-speed, has 3.73 gears in it.

pulling 14K getting 6.8MPG on average (hand calculated) has a intake, but no muffler and i believe the cat is still on it. so why it it so bad? it had a bully dog torque dog on it on high. and it's not throwing any codes. should i remove the cat? or what i really need better mileage.

and i pulled the bullydog off just to see if that's the problem

 

Maybe as the engine gets broke in your milage will increase. My 2500 5.9L is getting 21-22mpg hwy. 70000 mi. I am removing the cat this weekend.

 

I'm not getting that great of milage also in my 06 unloaded but it might be it has a fresh remaned short block. I'm hoping when I replace factory muffler and work the cat I get better milage

 

with my 6.7 i get 13 pulling 16,500lb travel trailer when i was mostly stock i got around 7-8

 

Get a smarty!

 

What are y'all running as far on the smarty? I have a pod and it doesnt seem to help

 

u were pulling 14k and got 6.8 with the bully dog on high? have u checked ur milage since then? u should never pull that much weight with any programer turned on high. has it always got bad milage? what does the truck get unloaded?

 

I bet EGT was through the roof and at least 3mpg went straight out the tailpipe in the form of black smoke.