th400 automatic with V6 engine

I have been offered a bone stock Commando with the automatic behind a V-6 engine.

It has the adapter behind the bellhousing for the th400.

The seller tells me that this is a part that a lot of people want and is hard to find.

I'm not familiar with the jeep automatics, but if the part is a part in demand, it'll be one more reason to buy the commando. All I want is the engine and exhaust.

Now, I didn't post this in the Commando section because I thought that it would be easier to catch someone who knew something about it here, and it is kinda of an ersatz V-6 queston.

kamel

 

Do you mean the ring adapter between the TH400 and the V6 or the T-TC adapter? The transmission is a vanilla TH400 with the Buick "nailhead" case and an output shaft for the Dana 20. There's an adapter ring between the nailhead case and the V6 that changes the nailhead pattern to a BOP pattern. The combination of the nailhead case and the ring adapter is equivalent to a BOP TH400 case, which was used in many thousands of GM cars. The ring adapter might be of use to someone with a J-truck or Wagon with one of the early AMC engines that wanted to convert to a BOP engine, since they use a nailhead TH400 with one of two adapter rings to the Rambler patterns (232 or 327). Saleable, but not a huge demand.

The TH400-D20 adapter is worth having; that and the TH400 tailshaft will adapt a D20 to any TH400 (ie Chevy).

 

Busted!

 

More Jeep trivia - the adapter ring came in 4 patterns, nailhead to 1) GM BOP (225, 350), 2) Rambler OHV 6 (232), 3) AMC Gen-1 V8 (327 Dauntless), and 4) AMC Gen-2 V8 and AMC I6 (258, 304, 360). From 1971 to 1973 AMC used the nailhead TH400 in their Jeeps, whereafter they started using a TH400 specifically for the AMC engines. The BOP ring could also be useful to someone that wanted to put, say a Caddy 500 (a popular swap) in their 71-73 Wagoneer or J-truck.

Jeep used the nailhead TH400 in the whole line from 1965 till 1973, after they phased out the Borg-Warner automatic. I suppose using these ring adapters was cheaper than having GM cast TH400 cases for each of the different engines used...

 

Excellent info Timgr! Don't forget that some applications also used a crank spacer/adapter needed also for the flex plate. Nickmil.

 

There's a few more adaptors than that. The "nailhead" TH400 was called the "Universal TH400" and also had adaptor rings for Jag and Rolls Royce . All of which used the TH400 for a time.