I recently bought a 79 chevy dually crew cab 4x4. Has 454, 4spd, 205 T-case, Dana 60 front axle, Dana 70 rear. Before I bought it I was told by the owner that someone before him had changed the rear end gears out. The truck was originally 4.10 gears all around. For whatever reason someone left the 4.10's in the front and put 3.73's in the rear. He said he never needed 4wd and just used the truck to pull a large fifth wheel camper in the summer.
Anyway I can't obviously use the 4wd until I swap the gears out. I'm wondering what you guys think. Should I leave the rear end 3.73's and swap the front to 3.73's also or should I leave the front alone (supposedly 4.10's) and get 4.10's for the rear?
I suppose it's personal preference on what gear to use. Would I notice much of a difference either way? Right now the truck has 235x85x16 inch tires which are about 31.7 inches tall. I'm gonna stay real close to that size, maybe up to a 33" tire but no bigger than that. I was just wondering with the factory tires probably being about 31 inches tall and original factory gearing being 4.10 if I should go with the 4.10's?
My buddy said with all the torque of the big block I wont see a noticeable change in the two ratio's anyway. What does everyone else think? I usually don't pull heavy trailers too often. I just have a race car/trailer to pull and might see some other heavy stuff once in a while. And I only get about 6-7 mpg now so I know fuel economy isnt the issue. Just want to know If you guys think I'd be more in my powerband with 4.10's. Okay enuff rambling I'm ready for some input. Thanks for your replies as always.
Matt
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