TVR differential question(s)

[94Griff500]

I've got a 36k miles mid '94 Chimera/Griffith GKN differential that feels to have too much "play" as measured by being able to rotate the driveshaft input flange from about 12 o'clock to 2pm with seemingly little / no movement at the axles. That seems to be an excessive amount of play / clearance assumably at the ring to pinion shaft contact point.

I also understand that the '95 serpentine engine & later cars switched to a BSR (?) differential, and that parts and service on the prior GNK differentials are expensive or unavailable?

Can any one shed light on their experience with servicing a GKN?
What about the input "play" described above: is that normal or excessive?
I've read somewhere that either of these differentials are very difficult to remove? Is the GNK worth a removal / takedown?
What is an acceptable amount of input flange rotational play? Where & how is that play adjusted?

As always: Thanks for any advice!

[sixor8]

I can't advise on maintenance but thought I could add that the rear diff used from late '96 (ish?) was the BTR. There are brackets available for one to be used instead of the GKN if you wish.

https://www.centraltvrparts.com/product/centre-dif...

Other suppliers are possible. Racetech seem to have mounting parts for both:

https://racetechdirect.co.uk/transmission/differen...

[PabloGee]

These are the name in diff rebuilds, they did my GKN, and it’s fine.
http://www.readmanracing.co.uk/

Two things to note:
Ask them about fitting the later back cover with the full and drain plugs on the side - it makes oil changes a million times easier.
Get the right polybushes when refitting - the fronts are different from the later BTR diff :

https://motaclan.com/product/bush-gkn-diff-early-g...

And the rear:

https://powerflexstore.co.uk/tvr/griffith-chimaera...

[Sardonicus]

Pinion bearings probably worn IME causing the lash/slack you have experienced on your GKN not a worn crown-wheel and pinion assy often blamed for this condition , so a set of bearings of the pinion and carrier should see you alright not a DIY job sadly , so long as its not been driven to destruction with ignorance to whining or growling sounds

Edited by Sardonicus on Monday 15th December 17:08

[Loubaruch]

Unless you have car lift I would not try and tackle removing the diff yourself as it is very heavy and has to be turned through 90 degrees to pass the chassis members. It is difficult enough with a lift unless you have a transmission stand to rest it on.

[94Griff500]

Thank you all for the insights & advice on my GKN differential.
I agree that pulling & service the differential is not a do-it-yourself project given it size/weight and mounts, so I'll talk to trans/diff specialists here in the US.
At least it appears that I can at least still get some internal diff parts for the GKN, as well as new / better mounts.
My son lives in UK so he can locate parts hopefully once I find a service provider here in the US.
Thxs again for the info & advice!

[keeling54]

The previous owner of mine paid nearly £600 to have their diff stripped and rebuilt. 18 months later I bought it and it leaks and whines terribly. This was the same reputable TVR garage that sealed a hole in the rear of the fuel tank with sikaflex.
Mine will need a rebuild shortly, but understand they are a real pig to get out.
Mine is a 93 so the early one.

[eff eff]

I have a 2002 Griff, I had the hydrotrack diff rebuilt because of excessive backlash. I was advised that some poly spacers used in the diff were worn and new spacers were no longer available. The diff was rebuilt with second hand spacers that were in better condition than mine!!

[Sardonicus]

keeling54 said:

The previous owner of mine paid nearly £600 to have their diff stripped and rebuilt. 18 months later I bought it and it leaks and whines terribly. This was the same reputable TVR garage that sealed a hole in the rear of the fuel tank with sikaflex.
Mine will need a rebuild shortly, but understand they are a real pig to get out.
Mine is a 93 so the early one.

Shocking oil leaks can happen but noisy ? NO thats just not good you can drop the diff out on axle stands an a trolley jack but if you have an helper its far easier and a ramp better still

Edited by Sardonicus on Monday 22 December 12:49