Hey guys, I bought a donor truck to put my 02 3500 back on the road. It has 3.55 gears in it and mine has 4.10s, question is if I swap gears how will this change my performance and MPGs. The truck is mainly used for a daily driver (60 miles one way, mainly 4 lane) but I do tow with it from time to time (about 10K lb). Right now Im getting roughly 20mpg highway empty, and has all the power I want. Will I be disaponted with the high gears?

 

I don't think so, I think you'll be happy with them. Its a 15% change, so RPM will be that much lower. Unless the engine is lugging, which is doubtful, you should see an increase in mileage. Of course the downside is 15% less pulling power.

 

If you mainly use it for commuting I'd say that 3.55s will do ya some good

 

Thanks, I may just change em, the donor is only a 4x2 so ill have to buy front gears, will 3.55s work on my 4.10 carrier (D60) or do i have to change it

 

I love my 3.55's and it's cummins when towing just put your foot into it if needed. I never had a problem pulling the 13k around with mine.