Need help boosting my MPG's

Gradual speed increase on flat ground to the bottom of a hill, minimum throttle to get up, let your momentum coast you over the top, coast down, lather, rinse, repeat.

Cut your losses and buy a modern truck.

 

Holy sheeet man 2.5 is ridiculous!
There's no reason you shouldn't be getting 5mpg.
Something is wrong there for sure .
What are you pulling for wieght and what are you running for rpm going down the freeway.

Does it pull ok . What kind of boost are you getting . Any smoke?
We need some more info if you want someone to help you.
Better yet , bring it back to cat as they did the expensive rebuild and put it on the dyno tell them to fix it.
2.5 is crazy . Sell it and buy a horse.

 

How are you calculating the MPG?

 

Charge air cooler massive leak?
Oh, how about replacing all the fuel lines. A truck that old could have some lines swelling on the inside restricting fuel flow. Not something you would see from the outside.

 

You in mountain country?

Head winds that wont quit?

Dragging brake or something else?

 

It's just not set up ( tuned ) right. You'll get some CAT experts to chime in, but I'd think 5 should be an easy to reach number. They just don't have it set right.

 

Even I81 is ok, There is a problem with Tuning, if such a thing is possible.

Other thought is the rings and compression perhaps. But that's reaching and fishing.

Take it back to Cat.

A paid for truck is a immense asset.

 

Was any pump work done, timing advance rebuilt or a simple in frame. CAT is having issues with the reman nozzles as well. What are you seeing for pyro temps as well as coolant? It should make the same power as well as mpg after the overhaul as before.

I will say for the most part most CAT shops don't have a man left with the knowledge or tools to get a B right. They have no feel for it.