[Bobalouie]

I look at it this way...newer trucks, like my dads 2003 Z71 are cruising about 2200 rpms at 80 on the highway using a 4L60E (same gear ratios as the 700R4) and a 3.73 rear end. The tires are P265 70 R16s (31.7 in tall, call it a 32). A theoretical gear ratio/speed calculator says that the rpms with that combo should be 2193 rpms, so the calculator is pretty accurate. If you want to cruise about 2200 rpms at 80 using 35s and an OD trans, you will need a 4.10 gear. The calculator says that you would be turning 2204 rpms. That puts the same strains/stresses on the transmission/drivetrain as a current model truck. You dont the the extra umph off road as a lower gear, but you get better economy everywhere else. And if you need a little lower gearing for some offroad work, drop the T-case into low.