Triumph Repair: TR7 differential problem, bad cv joints, specialised areas

Question
Dear Jim, I know this question might be a bit outside your specialised areas, but looking at your great responses, I thought you might help me or direct me where to find some help. My 1980 TR7 has been sitting in the garage for three months because I wanted to upgrade the standard differential to the 3.45 ratio. Finally, today I received the so much desired call to pick up the car... but the noise is awful! Whinning all the road long. The mechanic almost recognises he does not know what to do anymore. All relevant spares are new, but the noise continues. Do you know if there is something particular about these cars' differential? The guy deals with classics every day and he says never saw such a complex case. What can I do?

Thanks in advance for your help. Kind regards,

Fernando

Answer
Fernando,

4 speed or 5 speed?

Is it better or worse when you accelerate?  Back off on the gas?

Keep in mind that what might "sound" like gear whine can be caused by a variety of problems... anything from bad CV joints on the driveshaft to bad bearings in trans or diff to tire tread pattern.

If you can find a shop that has any form of dyno setup (standard or low-power emissions type) see if you can get them to run the car through the gears and pinpoint better where the sound is coming from.

If it's still in the diff let me know and I'll see what can be figured out.


Cheers,

Jim