View Full Version : TR6 Will a TR6 4 speed fit a TR4A

10-14-2006, 09:36 AM
Hi guys - will a TR6 4 speed bolt right on to a TR4A? My TR4A gearbox needs a rebuild but I've been told a TR6 box will also fit....

10-14-2006, 09:58 AM
Yes. Tr2 to TR6. Same Trany.

10-14-2006, 12:07 PM
While all TR transmission cases are essentially the same, care must be taken to insure the input shafts are of the same length and the end of the input shaft that goes into the flywheel pilot bearing are of the same diameter. The TR4A sleeve the throw out bearing rides on is the same as the TR6, but I would check it to be sure it is.

10-14-2006, 01:28 PM
Thanks guys!

10-14-2006, 05:02 PM
There is a difference in the thickness of the engine side of the bellhousing The TR6 is thicker so you will need longer bolts and adjust the slave cylinder(possibly) for the change too. Not all holes on the TR6 bellhousing will be used on the TR4 but the bolt pattern will fit the 4.

10-14-2006, 05:25 PM
Input shafts on TR4/4A boxes are longer than TR6's from what I have seen.

10-15-2006, 06:42 PM
I put a tr4 trany with OD in a TR6 and it worked fine, but as I recall I was told that the 6 trany into a 4 wasn't as easy a swap due to the input shaft length as swift6 mentioned. This was 30 years ago so I don't remember the fine details.

10-15-2006, 07:51 PM
I have an early TR6 gearbox in my TR4A.I don'recall the need to make any modifications. Aside from differences already mentioned, the 4A has a different shifter attachment setup on the top cover, and the 4a shifter does not have the same "bend" in the shifter.