Gearbox & overdrive advice

[boblange]

I am looking to install a reconditioned gearbox and overdrive in my TR3B (TCF series).

 

The unit I am considering is a 4-synchro box with 'A'-type O/D from a TR5. The vendor tells me the only difference is that the input shaft is slightly shorter but that the box can be fitted without adaptation. Can anybody confirm?

 

Also, can anyone recommend dealing with TR Shop on Chiswick High Rd. in London based on experience?

 

Thanks,

 

Bob.

[Fireman049]

Yes, I've dealt with TR Shop and received excellent and quick efficient service.

 

Tom.

[Guest ntc]

Depends on the clutch used and bell housing .

[BlueTR3A-5EKT]

Deleted. Wrong info.

Edited June 19, 2014 by BlueTR3A-5EKT

[littlejim]

If the gearbox and O/D are already matched you should be right.(??)

I swapped from no O/D to O/D fitted. The gearbox man had to change the main shaft in the gearbox in order to fit the O/D.

[Ian Vincent]

I think you will find that the bell housing flange on the later box will be thicker which means you need to apply a bit of leverage / ease out the holes in the bracket to make it fit

 

Rgds Ian

[vivdownunder]

TR3B had a fork release clutch but the TR5 gearbox will be set up for the later diaphragm clutch. The clutches aren't interchangeable, other than re-drilling an earlier flywheel for a later clutch.

 

Input shafts are the same. The gearbox front sleeve extension was 2 3/8" for fork release clutches, but shortened to 2" for the diaphragm clutch. The shorter front extension, providing it's in smooth condition, can be used with a fork release clutch. Just fit a prescribed release bearing and sleeve.

 

Best to also fit a new hi-tensile clutch fork to shaft pin, and wire it in place.

 

Viv

[Graham Harris]

You will also need longer studs and bolts for the bell housing if the casting is thicker.

Graham

[boblange]

Thanks for the clear explanations.

 

One further question: the vendor has a second unit with "Uprated thrust washers" for a supplement. Is this worth having?

 

I shouldn''t be so ignorant but it's been 30 years since I last touched a gearbox. I'm looking to set the car up for some reasonable European touring (300-400 miles a day).

 

Bob.

[BlueTR3A-5EKT]

Updated thrust washers?

That may mean NOS OE THRUST WASHERS.

or

If you can get the serial number it may be a stag box. Look for LD prefix. That would be a bonus as it is an altogether stronger gearbox to start with.

Stag box used roller thrusts on the lay shaft thrusts rather than the plain bearings on TR boxes.

Cheers

Peter W