T90 transmission
Posted: Fri Mar 23, 2012 6:21 pm
What is the difference between a t90 a-1 transmission and a t90 transmission?
Jeep used three versions.
From the Novak site:
http://www.novak-adapt.com/knowledge/t90.htm
T90A1
The T90 used from 1946 to 1962 with the L and F-head four-cylinder engines is designated as the T90A1. These versions all feature top shifters, a 7" input shaft (stick-out length) with 15/16" x 10 splines and a felt-sealed front bearing retainer assembly. The input shaft has an 18 tooth, helically cut input gear. The cluster gear has a 33 tooth driven gear, resulting in a 2.79:1 first gear and a 1.55:1 second gear.
T90C
The T90 used from used from 1963 to 1971 with the F-head four-cylinder engine is designated as the T90C. It features top shifters, a 7" input shaft (stick-out length) with 15/16" x 10 splines and a felt-sealed front bearing retainer assembly. Since the T90C uses a case marked "T90A", you will need assurance that the transmission in question came from a post-'62 Jeep, or you will need to pull the top cover and count teeth. The T90C has a 16 tooth, helically cut input gear. The cluster gear has a 35 tooth driven gear, resulting in a 3.34:1 first gear and a 1.85:1 second gear.
T90J
The T90J was used with the six-cylinder trucks from 1952 to 1965. These were either column or floor shift models. They had an ~9-1/4" input shaft (stick-out length) with a 10 x 1-1/8" splines and a neoprene-sealed front bearing retainer assembly. The T90J has an 18 tooth, helically cut input gear. The cluster gear has a 33 tooth driven gear, resulting in a 2.79:1 first gear and a 1.66:1 second gear.