TR6 CV driveshaft failure

[SteveBaker]

Has anyone had the experience of losing their rear hub in a corner, potentially pushed off by a CV drive shaft? I have heard that on full compression the shaft itself is too long and will try and push the hub off. Unfortunately, I have had this happen 2 weeks after fitting CV shafts. Unsure what to do going forward. I should add that this is on a TR6 chassis.

Edited October 2, 2025 by SteveBaker

[Andy Moltu]

No.

Did the studs come out of the trailing arm.

CDD now advised checking the measurement from diff to trailing arm to check for chassis differences after repairs, but their concern is more about the need for a longer shaft (spacer). The CV joint is held onto the splines by a simple circlip. I’d be surprised if this could apply enough force to push off the hub. However if someone has used power tools to attach the hub to trailing arm and stripped the threads…. Should be 14-16 ftlbs only.

[trchris]

Hi Steve I’m with John it’s more than likely the hub retaining studs in the trailing arm have pulled out possibly by over tightening on assembly? Or the threads were weak after years of service hope you escaped with minimal damage 

Chris

[trchris]

Steve It may be prudent to talk to the supplier as well 

Chris

[Waldi]

Steve,
Is this with a CV drive shaft set of CDD?

1) If so, have you carefully followed the installation instructions and done the axial “face to face” measurements between diff flange and trailing arm mounting flange? This is especially important if you have a modified rear suspension set-up )like lower ride height or telescopic dampers).

2) Have you applied the correct torque to the 6 studs in the TA? (meaning not over-torqued the studs in the trailing arm? They are easily pulled out).

3) The rubber end stops (2 of them limiting the upper - and two of them limiting the lower position of the TA) need to be installed as well, otherwise the travel may be too much. If the original Armstrong dampers have been removed, the lower end stops does not work anymore so you are dependent on the telescopic shock length to restrain that position.

Waldi

 

[harrytr5]

Steve please come back with your findings and the manufacturers of the CVV and what did they come up with.?

Most of us are running around with CVV joints in NLG and have for years.

I also think the same as others but how can the hub come off when bolted through as assumed it was a fail safe desighn

Regards Harry

[Andy Moltu]

The hub isn't bolted through the trailing arm. It's located by six 1/4 unf studs into the alloy of the trailing arm. Lot's of threads about what a fundamentally daft idea this is! Helicoil or fit UNC studs.

Or do you mean the hub has come apart at the stub axle? The CDD ones are meant to be torqued up to 215ftlbs. Which if FT+++.

[trchris]

If and it’s a big if l were to fit cv jointed drive shafts as a course of action l would change the hub retaining studs to 3/8th UNC

Chris

[harrytr5]

The original hubs have had their day. Design life no more than ten years from new I would hazard a guess.

Our TR,s were not designed to last this long and manufacturing must involve to keep on making new cars to sell on to survive.

My Dad worked for Triumph's and owned and drove their cars. I have always had Triumph's from motorbikes to TR's and its more than a hobby to me.

I have had many BMW motorbikes and the last motorbike was a modern three cylinder Triumph Thunderbird which was little used as the wife gave up on being a passenger.

My TR5 is a keeper of which I fully restored and back on the road in 2004 .Bought as a wreck in 1998 but even then I saw the beauty that it was to become in later years.

They exist because the owners of the day loved them as we do now.

Regards Harry

[Paul Hig]

20 minutes ago, harrytr5 said:

The original hubs have had their day. Design life no more than ten years from new I would hazard a guess.

........

Regards Harry

Take it you are running CV joint drive shafts on your TR5 then Harry

[harrytr5]

16 hours ago, Paul Hig said:

Take it you are running CV joint drive shafts on your TR5 then Harry

Yes.

Regards Harry

[JohnC]

FWIW I have splined shafts with roller bearings in mine. I had them fitted soon after arriving in Australia about 30 years ago and they've been fine ever since. An annual application of the grease gun and that's it. They came from a Datsun (180? 120?) and need a funky UJ to fit the TR6 yokes (bearing cups are larger than regular TR6). I suspect those parts are no longer available even from a scrap yard, but it's all there was at the time. There were certainly no CV joints for our cars, and I think even new splined shafts were hard to find.

JC

[spiro]

Mine gave way but at Diff end I suspect the bolts came loose and broke the aluminium case. These were NOT CDD shafts which is what I'll fit once TR returns from current location Portugal. They had been on since 2004 they were GermanAustria manufactured Innsbruck.

I never had any issue with CDD driveshafts I have been fitting them to TR's and Stags for well over 10 years

 

[harrytr5]

And the outcome Steve is....

Regards Harry

[Paul Hig]

Diff seals and bushes replaced, CV shafts supplied by CDD. Bit of a fiddle to get them between chassis and diff, but went straight in. Everything aligned an nipped up (still needs touquing to correct settings), but no adjustments necessaryas all clearances ok 😀

Also fitted new flexi brake pipes and brake pads whilst at it

 

All went better than expected, so happy lad

Edited October 14, 2025 by Paul Hig

[harrytr5]

and lovely rose jointed drop links that are far superior the stock rubbish ones

[michaeldavis39]

Paul- quite a few of those locknuts have no thread going through the nylon

Edited October 15, 2025 by michaeldavis39

[TR NIALL]

1 hour ago, michaeldavis39 said:

Paul- quite a few of those locknuts have no thread going through the nylon

They don’t look as if they have been tightened up yet.

[Paul Hig]

1 hour ago, TR NIALL said:

They don’t look as if they have been tightened up yet.

They hadn't. All done now, 1st time with a wheel at each corner since the M6 incident back in July

(I know the paints not good and it needs redoing 😳)

Edited October 15, 2025 by Paul Hig

[harrytr5]

Steve,

Have you had chance to asses what went wrong and the outcome of that. You could PM me if too sensitive of course.

Regards Harry

[Waldi]

@SteveBaker:

Steve,
given all the tips from others and the fact that others may have a similar issue (but are not aware) can you give an update?

Thanks,
Waldi

[Paul Hig]

1 hour ago, harrytr5 said:

Steve,

Have you had chance to asses what went wrong and the outcome of that. You could PM me if too sensitive of course.

Regards Harry

Try this thread for the failure on my car ...  

 

[Paul Hig]

Update ... Test drive out then back into garage!  

Brakes need rebleeding and some adjustment

Need to look into engine miss fire. Prob sticky injectors as first start sing incident in July

[stuart]

4 hours ago, Paul Hig said:

Try this thread for the failure on my car ...  

 

Its the CV failure that Harry is trying to find out about. Yours is hub failure the way the originals fail.

Stuart.

[harrytr5]

Thanks Stuart, just waiting for Steve to come back as it is kinda important to find out what happened.

Here's hoping.

Regards Harry