Found another nice '78 Crew cab 2wd, originally 6cyl, 4speed 4.10 truck, now a 383 4bbl, A833 4speed truck. Have a '93 cummins donor truck with a 5speed, have either a Dana70 3.07 gear or Dana 80 dually 3.55 gear. What do 250 crew cabs come with, dana60 rear? What to do?
-J

yes, it would have a dana 60 rear in it....
if it were me....I would go with the 3.07 rear end...have awesome fuel mileage, and pull in 4th gear....have 5th for going home...

What's the gear ratio on the 5speed OD? Is it higher than the auto? I know the OD auto A518 is like .69? Could a guy get 22-25mpg with a 3.07? I think adding a dually would only add weight, and decrease mpg eh?

the auto o/d ratio is better, if you can get a good converter....
yes, 22+ is not out of the question...

Thanks Sam, I think I'll do that 3.07 gear. My '92 cummins auto 4x4 is a great for the winter and pulling trucks off the hillside but man it's a rough ride, the 2wd trucks ride so much nicer for highway driving... Those autos must have pretty loose torque converters, they're kinda of a dog but they always pull just can't be in a hurry..
-J