Trying To Find The Best Set Up

[harleydavee]

Looking at adding another truck. Looking at a 2001 Mack CX613 with 460, 13 speed Eaton, 3.90 gears. also have a choice of 2001 CX613 427,fro 10 speed, 3.73 rears or a 2003 CX613 460P, 13 speed eaton, 3.90 gears. both 3.90s have tall 22.5 tires and the 3.73 has lo-pro 22.5. We run midwest corridor(Mn- Tx and Oh- Denver) with very few mountain runs. I would prefer 3.55 gears for fuel economy but have read where could hurt performance. Looking for the PERFECT (lol) setup. any ideas? We also haul weight sensitive loads so trying to stay somewhat light weight.

[usmcjimbo]

Ideally no matter what your engine/transmission/rear end is, on an over the road truck you want to be running at between 1400 and 1500 rpms at your desired cruise speed, which for nearly all large fleets is 65-70mph

Personally I was always a fan of direct drive set ups in high gear, but everyone has their own ideas

Performance and hill climbing ability will always be a function of increased fuel consumption

[Gambi80]

The trucks with 22.5 talls and 3:90 gears probably won't be any different than the 3:73 and low-pro 22.5's going down the road...far as speed/rpm's go. The 10sp will be about 100lbs lighter. Personally I'd go with the most gears and power. lol

[harleydavee]

thanks for your input. My 01 Vision gets better fuel economy if the driver keeps it in the 1350 rpm area. Didn't know if the 460s were the same or had a different sweet spot? Put tall 22.5 rubber with 3.73 rears on my CX613, the driver likes them since he can run slower rpms and still maintain some speed.