The '55 1st series rear end had a 3.90 ratio, with 4.11 as an option. It's
easy to check - just pull the cover, count the teeth on the ring gear, and
divide by the number of teeth on the pinion gear. Tire size does effect
final gearing but broadly speaking, either 3.90 or 4.11 is a good ratio for
a .70 overdrive.
51 GMC 1/2 ton
Winter Park FL
----- Original Message -----
From: "Deve Krehbiel" <email@example.com>
To: "OleTrucks" <firstname.lastname@example.org>
Sent: Thursday, October 26, 2000 6:22 PM
Subject: [oletrucks] 55 1st Rear End
> Since 1955 1st series was the first open driveline, I am hoping they also
> increased the gear ratio. Can anyone tell me what a 55 1st 3100's gear
> is in the rear end? Also, what would you suggest for a 261 engine with
> overdrive transmission and that rear end for an optimal gear ratio?
> Is there any way to tell the gear ratio yourself?
> Deve Krehbiel
> Hesston, Kansas
> 1950 3100 * 1949 3600 * 1948 4400
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959