MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - J Type overdrive

I have a 71 TR6 and I am thinking in putting a J type overdrive unit. My question is will I have to install a new backet to the frame to suport the rear of the transmission? I have been told I have to change the tail shaft of the transmission to match the install for the J type unit.
Allen
Allen Bradley

Allen,
I just installed an O-drive on my '76. First, on a '71, your rear mount is different from mine so I am not sure but on '73 going forward you could use the existing mount. The frame changed in that year so maybe someone else can help you on the mount. In regards to the rest of the installation, it is pretty easy. In addition to the j-type unit, you will need a mainshaft,to replace the mainshaft in your non-overdrive unit and adapter plate to connect the unit to the gearbox. If you are converting your existing gearbox, this is an excellent time to rebuild your unit since you will have to take the whole thing apart to install the new mainshaft. It is not as scary as it sounds. Also, if you pick up a non-tr6 o-drive (say from a sedan) the holes in the rear flange will not match up but that is an easy fix, just have them redrilled.
Michael Parkhill

Hi Allen
First off a '71 came with an A type OD. J type was installed from CFXXXXX on. But any OD is better than no OD. Yes the rear tranny mount is different. Now the problem. It appears that the A or J type mount is no longer available. Maybe u will get lucky with one supplier having it or some friendly sole out there has a spare and is willing to part with it. Yes the MAINSHAFT of the tranny must be replaced. This shaft is N/A for A type but looks like it is available for the J. You will also need the angle drive for the speedo and 1 interrupter for the gearbox top cover. I would NOT install an OD without the interrupter. J was designed to operate in 3rd and 4th while A was 2,3,and 4th and both would NOT NOT NOT NOT operate in reverse!! The reverse lamp interrupter is used for both A & J. Also required is the wiring to the interrups and the solinoid, the OD switch on the steering column and the switch escutcheon. It appears that the J type does not require a relay but a J type owner might want to shed some light here. My A type does have a relay.
Others please comment on wether the engine requires pulling or not...I was lucky...had the tub off when engine went in. For sure, the tranny must come out to install the new mainshaft.
Good luck Allen... u will appreciate the lower RPMs at speed.
Rick C
Rick Crawford

Allen
Check out following site re a J type OD in an older TR6 frame.
http://www.buckeyetriumphs.org/technical/JOD/AdaptingJOD/AdaptingJOD.htm
Rick C
Rick Crawford

Michael and Rick thanks for the info. I have decided to buy a J type of overdirve for my 71 TR6. I will give you an update how it works out.
Thanks again
Allen
Allen Bradley

Allen
You will not regret it. It will only take you a little more to install it.
Rick C
Rick Crawford

This thread was discussed between 13/06/2002 and 16/06/2002

Triumph TR6 index