The Cummins is a "P" pump Engine and yes, it should be doing better than 10 mpg. But if you know anything about the AT 542 transmissions they are a 1:1 4 speed non lock up torque converter. I could only regear the Dana to 3:56's ( I did put a locking diff while I was in it.) so it still needs an overdrive. Such as the .74 on the MLD6Q I'm wanting. I have a rock crawler rig and like to get as far back in the back of Moab Utah as I can get for a base camp. So that's why I want the manual. And it will give me better mileage. The Old Girl is 16.5 K lbs so we're talking alot of mass to push through the wind. I can only use propane in the diesel as a power adder. Which is a lot like putting NOS on a gas motor. So not a big advantage for it on my application.
Sorry, I don't hang out here much on a daily basis. So I just saw your question.
And since you asked!
Yes, I put in a very healthy 5.9L Cummins in it, that is putting out an estimated 350 horses. It was like building a full size ship in a beer bottle. Quite a tight fit.
The transmission we're using for now is an Allison AT 542 out of a rear drive Class A. This swap has upped out fuel mileage from 6 mpg to 9~10.
We are planning on swapping it out for an Isuzu 6 speed manual MLQ6 D.
It's a cable shift tranny that will make hooking it up through the basement a breeze.
My plans with the cable shift is mounting the shifter to the side of my Drivers Seat so it will swivel with the seat when I want to exit.
That transmission has a granny 1st which I need to get out of some of our favorite places in Utah and Colorado when we go 4 wheeling with my Toad. And it has a .74 OD that puts my engine right in it's powerband at 70 mpg. The Isuzu trans should bump the mileage up to 14 mpg.
Curtis
