1971 J-2000 transmission identity

[gcbc]

I have a 1971 j-2000 truck w/44,000 miles and an auto trans. w/no reverse in it, guy I bought it from said it just quit one day. I know it is a TH400 but have had alot of stories as to what years will replace this model. Anybody know what years will replace a 1971 TH400? Thanks in advance - gcbc

[J20 project]

gcbc,, 1966-1973 will match up, although be careful on the 73 end of things, there were some 73 1/2 tranny/trans setups which were the next style for 74 and on. At any rate, if the th400 you find used doesn't have a 2in adapter between the engine and tranny then it is the next newer style. It can be used but you would have to change the tailshaft and may find some tranny mounting issues. J20