TR2/3/3A Drive shaft question

[Linoman]

This fall I'm planning on switching out the non-syncro nonoverdrive tranny for a TR4 full syncro with overdrive. Will I need a different drive shaft?

~Tim

 

[charleyf]

The answer is no. The drive shaft has a sliding spline that allows it to move forward and back in length.
But you will need to modify the rear tranny mount. You will need to elongate the two bolt holes to the rear by about 5/8". You may also need to grind off a bit of the raised portion at the rear of this plate if it interferes with the tranny.

 

[Linoman]

Thanks Charleyf, wanted make sure I wasn't going to need anything major beyond the tranny, wiring, switch, and solenoid.
I'm looking forward to this upgrade, every time my wife or I are out for a drive we find ourselves trying to find 5th gear.

 

[CJD]

If you’re current tranny is an early model, you may need a different flywheel, starter, and tunnel cover.

 

[charleyf]

Your profile shows a 1960 TR3. So I would guess that you have a commission number car after TS50000. That should mean that if your car is stock your flywheel,clutch and starter are all compatible with the TR4 tranny. You will likely enjoy both the full synchro and overdrive.

 

[Geo Hahn]

You will, of course, need to swap your TR3 gearshift lever over to the TR4 gearbox.

In case you do not know, there are a couple of additions that some (me) feel are a good idea here. Adding a diode to make life easier for the relay and adding a fuse (I used a slo-blo) to protect the wiring should the the solenoid pull-in circuit fail to release. Several threads here on both - credit for both ideas goes to our late friend Randall.