View Full Version : TR4/4A TR4 Tranny in TR3A

07-11-2009, 07:45 AM
I have a TR4 tranny in my TR3A and also have the original TR3 Tranny and was wondering if the shifter from the original Trans will fit the TR4 tranny without mods?? I ask first because I will likely have to drill out the retaining bolt which has broken of on both sides due to P/O neglect.

I was thinking about switch for two reasons:
1) The chrome on the original is in better condition and of course is the straight shaft (original)
2) A year or so ago my son gave me a walnut shifter for the 3A not knowing that the thread is not the same as the TR4 tranny I am actually using.

Optionally, I was wondering if thread conversion inserts are available (as they were many years ago)???



07-11-2009, 08:06 AM

It should. When I first restored my TR4A, I put a TR3 overdrive transmission in it to get the overdrive and I don't recall that I had the straight shaft so I must have swapped the shafts (course that was 25 years ago so maybe someone else who has done it more recently can speak more reliably).


07-11-2009, 08:07 AM
AFAIK, the shifter from the 3 will fit and work on the 4. You should be able to simply drive the broken retaining bolt out as it is a through bolt and not threaded into the shift housing. It may take three hands as the shift handle is spring loaded and will be putting an upward load on the handle.

Don't know about thread inserts. Swapping the shifter negates the question anywho. Good luck.

07-11-2009, 09:56 AM
:iagree: The shift lever will fit.

The only conversion inserts I've seen for many years are nylon and not very satisfactory, IMO. Don't know of a source for just the insert, either.

07-11-2009, 10:13 AM
The threads on the TR3 shifter (at least mine) are a non-standard size...7/16"-32...very fine threads. Even my machine shop supply that can get just about any size, couldn't come up with a die for that, although, they are available on-line if you hunt around. I just used a thread file to clean the boogered up threads on my shifter.

07-11-2009, 10:49 AM
The threads on the TR3 shifter (at least mine) are a non-standard size...7/16"-32...MMC has them, for a price.
So did Rutland Tool when I checked (which was a long time ago).

07-11-2009, 11:35 AM

I'm surprised you didn't check Enco - you pointed out that excellent site to me before! They have them for about $13!


07-11-2009, 01:55 PM
Yes the shifter will fit the TR4 box. I have a 4 box in my TR3 and I use the original shifter.

07-11-2009, 02:52 PM
I'm surprised you didn't check Enco -I'm equally surprised that they have them! Shame they don't also have the M5x.75 die for the speedo & tach studs, as I was just about to order one.