I finally got a look at the i.d. plate on the right side of my TH 400 and found the following: 77OD36463

Is this correct for a TH 400 in a '71 Cutlass SX, or do I need to look elsewhere for another stamping?

The previous owner said he did have the trans rebuilt at one point, but I'm not sure if they did an exchange, or rebuilt the original unit.

Is there a partial vin derivative stamped somewhere else on the cases?

 

After doing a little research, I found the i.d. plate is located on the right side of the car, and the OD designation is correct for a '71 4bbl, 455, dual exhaust, non-W car. The vin derivative is stamped on the left side. But the numbering (77) makes wonder if this was an exchanged unit at rebuild time. I guess more research is in order, but any other guidance would be welcome.

 

That 77' worries me.
Usually that's the year stamping.
The OD valve body code sounds right, but it's probably a 1977 trans.

Here's a tag from a 71 vette. and the Vin on the opposite side of the trans.

 

Just guessing here again, but did you get a real good look at that "77"? Are you sure the second number is not a "1" instead of a "7"? the ones have that little tail on top that might make them look like a "7". If the tranny is out of the car seeing what's there won't be a problem. But if it's in the car and you are trying to read it from underneath, at an odd angle, it might be worth a second look.

Randy C.

 

Verify whether the second number is 7. If it is actually 77, you have a swapped out transmission case. According to the 71 CSM your TH400 should be stamped 71 - OD - 36463. 71 is the model year. Are you sure it's not just all grimed over and hard to read? The OD trans was used for 455 4bbl cars. This info is provided on the 71 CSM page 0-5

 

Yeah, I better check that plate again to see if I read that number correctly. I am curious though, because there was only one terminal on the trans kick down switch, and the new wiring harness had two wires. I got the right one connected, but I guess the other lead is for a TCS function (?)

Either way it's good to have it back on the road, just in time for some Arizona winter cruising.