Rear hubs, driveshafts choices: stick with UJ or use CV?

[Paul Kelley]

I would welcome feedback from any of you who have replaced or upgraded your hubs and driveshafts. In particular it would be good to get opinions on whether the extra cost of CV products is worth it for everyday use.

Purely for safety first reasons, I am looking to replace my original rear wheel hubs. They are known to break up with age fatigue and the consequence of a lost wheel is potentially lethal. The post on this forum ‘Could have been worse’ (29th Aug - Andrew S) makes the point.

On researching the market for options, I have decided to eliminate reconditioned units because their provenance is uncertain and the effectiveness of a refurbishment seems questionable and therefore doesn’t fit my ‘safety first’ criteria. This appears to leave two main options:
1. Buy new hubs only, keep existing UJ driveshafts. Cost just under £600 (Rimmers)
2. Buy new CV driveshafts plus new hubs. Costs £1,000 - £1,200 (CDD, EJ Ward, SC Parts)

Cost/benefit thoughts and advice most welcome. Thanks
Paul

[djw113uk]

I have been investigating the same thing. I have talked a lot to CDD and intend to buy via him. My issue is that I have the BMW diff in Triumph subframe (not weslake), and I already have Datsun driveshafts. It does not appear to be possible to fit 'new hubs' onto Datsun driveshafts I also have Rover 800 wheels so am running 20mm spacers, so SC had a issue with guarantee under the 'extra stress'. CV's do not have the degree of flexibility that you have with triumph style sliding shafts, and there are a few posts on here about the care needed when jacking up the car.

I felt SC were just selling a product which they bought in, whereas CDD had built the units himself, so had better product knowledge. My only concern is I do 30k miles a year and I cannot find any long / proven history for any product, so I feel I am to be the high mileage guinea-pig! Whilst the old hubs do fail, they have lasted 40 years, and fail rarely. The new options are all new - and we all know how many poor quality parts are about.

I would like new hubs joined to my Datsun shafts, but Quaife hubs are dearer than shafts and hubs from other sources, and I would still need to find the right hub adaptor.

I haven't heard anything bad about CDD yet.

[Tonyw]

I have recently bought CDD drive shafts and I am very pleased with them. Alasdair is very helpful and if you visit his workshop you can see how precise his work is, how clean and tidy his work area is and he will talk you through the way he builds the units. I looked at others but some are the CDD ones marked up and sold on and the others don't seem to have the same customer care / time to talk with you.
I was reluctant to spend so much but if you consider how much people spend on painting and this is a safety item what can I say. ��

Tony

[Motorsport Micky]

Good decision, the rear hub replacement is a sensible safety upgrade.

Check out the TR Register forum for info, they share the Innsbruck rear trailing arms with the 2500 range and Stags, you'll find lots of feedback on most of the various driveshaft products, and TR owners lean towards accelerated (no pun intended) testing, ie !
" like the driving of Jehu the son of Nimshi; for he driveth furiously".

The current thinking is that CV driveshafts can suffer from being overextended if the rear shock absorbers are disconnected to allow full trailing arm droop (for rear spring removal etc). This can be avoided by disconnecting the driveshaft end attached to the diff and pulling the flange off the bolts so avoiding the driveshaft being overextended (and CV balls popping out of their tracks) when the trailing arms are dropped. The ride of CV driveshaft cars is almost universally acclaimed removing the transmission clonking and all of the infamous Stag twitch scenario of power applied early locking up the driveshaft and being released when the power is removed.
If you are still unsure about the proposed long life of CV drive shafts you could fit new hubs from your choice of supplier and attach to Rilsan coated sliding shafts or "Proptech" driveshafts which are the current "weapons of choice" within the TR Register for owners using the TRs in competition (sometimes severe). The hubs being bought in the Register seem spread between the CCD offerings (the cost of which for 2 x new hubs and CV Driveshafts is about £850 which owners like the perceived quality of but because of newness so far haven't achieved "Starship" mileages on, or offerings from the TR Shop ( I believe supplied by Bastuck a German TR specialist, (these also have only "restricted proof in use" evidence) or Goodparts in the States). Hubs are available from all these suppliers without driveshafts but will then "marry" up to your chosen driveshaft offering.
The Goodparts offerings are well known having been around a for a few years with good reports and achieved competition usage (at least 30,000 miles), so a few options to consider.

Micky

[bullstarz]

I had some Datsun one's made up seem fine, but now I'm one the way to developing a set Nissan GTST ( SKyline). The have been machined to fit the Stag trailing arm, CAD is done for the adaptor plate to match them to the diff. I'm just waiting for the EN24T steel to be delivered. All that will be left then is to get the drive shaft mocked up to the correct lengths then send them away to be made.

It's not been cheap but they will be strong, very strong.

[Paul Kelley]

Thanks for the information one and all. I'll check into Micky's other hub options for fullness but at the moment I'm leaning towards the CDD CV and hubs option.
Cheers
Paul

[djw113uk]

Bullstarz..."I had some Datsun one's made up seem fine"
Did you get modern hubs connected to the Datsun shafts? - How please and which ones? I don't want to get involved with tridat UJs! Are yours now 'available' if you are pursuing something else?
Thanks

[bullstarz]

My Datsun drive shaft have standard stag hubs. They are better than the Stags as they have ball bearings that allow the shaft to move under acceleration and braking. A local engineering company mated the two together, they said it wasn't easy as the two sets of holes for the UJ to were slightly different.

They will be a available once the new ones completed.

[mike@thenook]

My Datsun driveshafts are also mated to standard Stag hubs, the hub and diff yokes had to be made bigger to fit the bigger UJ's apart from that there's no difference

[DJT]

My Datsun driveshafts are also mated to standard Stag hubs, the hub and diff yokes had to be made bigger to fit the bigger UJ's apart from that there's no difference

Same here.

[Ctwidle]

+2
only difference was that I welded up the four bolt holes in the Datsun diff yoke and redrilled them to the stag pattern. I did this because my Stag diff yokes didn't have much spare metal to bore out for the Datsun bearings. I also needed to make up 1.5 mm thick 'washer' as the Datsun spigot has a smaller Dia than the Stag diff.

In the UK is it necessary to have such mods inspected and/or advise your insurance company?

[Motorsport Micky]

Only if you are very very wise,... breakage of driveshaft yoke or flange will allow a flailing driveshaft access to the bottom of the car and cause something that if it's not a mess will do until a real one comes along. Get out of jail card No 4 for insurers.

Micky