14 Mack, 4.6 mpg? Can I get better mileage with it?

The apps are underestimated for sure lol there's a few hills around here I can hit the bottom at 70 and be down to 20 within 1/4 mile

 

It can also be a Combination of things instead of one thing. Little by little they will add up.

drag, Chinese tires, improper psi of tires, brake bearing drag, improper tune.

one by one you have to eliminate the issues. Unfortunately dealer can’t help you since it’s deleted. I’m just surprised dealer sold a deleted truck. If you want speak to an attorney they Might be liable for that one.

 

You know not to be an **** hole but I am about these dealers, the dealer may be on the hook for the repairs and the replacement of any and all emission equipment because they pretty much broke both federal and state laws that cover dealers selling altered trucks. I can see a huge lawsuit against the dealer you bought it from no matter what you accepted, as in “as in” condition.

as of getting someone to fix the truck, well that may be the problem.

 

Not sure where you are, but, up here in Montreal is Diesel Spec.
They have lots if satellite dealers and I think they will let you send your ecm to them and have a stock tune installed.
Of course... "off road applications only"
I have been told, they are the best. Period. It would be nice to get it to them so they can tune it on the dyno, that's really the correct way. But they may be able to help you, or steer you to somebody who can.
Remember.
"Off road applications only"

 

The tall 24.5's are higher rolling resistance tho, and still the revs cant be all of it. The tires are maybe .5 mpg, compared to low rolling resistance tires. At that mpg he has a tuning problem with the delete. It really needs to go to somebody who knows how to delete, and how to tune. Then get the fine tuning, tires, air dam, etc done

 

Right. Elevation is certainly a factor like the mountains on the West coast but the grades in the Appalachians are a bigger deal IMO. They'll catch anyone slipping and they'll pay dearly for it.

 

I was going to trade in a deleted Duramax, and they said I would need to sign something saying it wasn't deleted to transfer liability to myself if there was a problem with the new buyer. But once I told them it was in fact deleted, they didn't want it at all.

 

Find a different tune

also tall 11 or 12 22.5s will drop rpm’s a smidge without having to buy different wheels,

 

A delete without a proper reprogramming is probably most of your issue.
Friend got a deleted truck and his milage was terrible until he found someone who knew how to tune and program it properly.

 

Private party they are worth more, not less.