Different truck and 20 years newer.... same may or may not apply.
The 2 speed Chevy axles up to 53 (that I know of) are all geared really slow, and limit top speed, but do allow you to (slowly) haul a lot of weight.
If a 2 speed is desirable or not all depends on your use and expatiations for the truck, and what exactly is the gear ratio in high?
It's a sure thing that the 2 speed from a 51 is slow; one in a 70 may or may not be to slow, or even to fast, for your plans.
Grigg
I drove mine home about 90mi, all highway, and it did OK cruising at 60-65mph. I guess mine may not be geared too low, because it did 65mph at a safe 2800rpm. My plans are to swap in my EFI 496 and a 6-speed Allison, so it should be even more highway-friendly.
My gearing is fine; I thought the issue was with the 2spd being less reliable or something...
I will be using this truck to haul my 36ft enclosed racecar trailer, or potentially a 46ft GN racecar trailer. My buddy pulls a 48ft GN flatbed hauler with his F450, and we "car pool" our rock buggies 3x or 4x at a time on it. I suspect I may be volunteered as the rig hauler on the next trip. lol
