Rear Driveshaft CV Joints.

[greymrj]

I guess they may be Chris but there isnt enough information in the listing. The listing doesnt say which grade high tensile or indeed the socket head type.

These bolts are of 'ultra' high tensile 12.9 grade, rather than the more common 8.8 high tensile. When you consider the amount of torque going through 6 x 8mm bolts with no other form of location (especially if a wheel spins then grips), you will appreciate that they have to be top quality and were designed that way.

They also have to take a considerable tensile load in some circumstances and are designed to be able to do so, very much the same as many of the modern, smaller diameter, cylinder head bolts.

Both the ones I removed (standard hex socket head ) and the new ones (12 point star, ) were marked 12.9 on the heads.

One small point for those seeking bling! It is not possible, at least as a standard item, to get stainless steel bolts to 12.9 specification.

Beware cheaper zinc coated imported bolts for this kind of job. Having driveshaft bolts shear or stretch would lead to VERY expensive consequences.

[ChrisGadd]

greymrj said:

Beware cheaper zinc coated imported bolts for this kind of job. Having driveshaft bolts shear or stretch would lead to VERY expensive consequences.

Noted

[Alan Whitaker]

Hi All
You should never use stainless caps on driveshaft flanges, should be 12.9. I have seen kit cars with them as a bit of bling but if they let go, well expensive repair.
You must use the plates with the bolts, lock washere are no good.
It's M8 for the 100mm flanges
It's M10 for the 108mm flanges.

Alan

You have a choice with boots regular with 2 clamps or bonded with 1 clamp, both are ok but with the bonded to look at the joint you have to remove all the bolts against removing a clamp

Edited by Alan Whitaker on Friday 28th March 07:22

[Kitchski]

greymrj said:

I am not sure why, but the actual Lobro bearing has a slight recess on one side which is supposed to go on the face AWAY from the gaiter.

It's because there is supposed to be a gasket between the CV joint and the output flange to prevent grease leakage. Not all joints have it, but most do.

[Kitchski]

glenrobbo said:

Richard,
If the old one is serviceable, don't throw it away, somebody may need one in the future, & Sierras are getting scarce these days.
Have you had the LSD overhauled with new special LSD oil packed & sealed into its' special chamber?
I may be talking total bx here, just something I saw on here last week.

Sorry mate, I missed this first time around.

Still have original diff, will likely sell it on ebay sometime soon.

Had LSD diff overhauled, yes. Didn't make a massive difference fitting it to be honest, though I suspect if I had more power I'd start to reap the benefits. Standing starts (the all of about three or so I've done since I finished the chassis!) are much better as it doesn't just spin up one wheel, and tends to just hook up and go. In normal pottering around, you notice no difference.

[Kitchski]

Alan Whitaker said:

Hi All

You must use the plates with the bolts, lock washere are no good.

Edited by Alan Whitaker on Friday 28th March 07:22

You'd better tell Ultima that. There are a lot of 700bhp + GTRs out there with no plates, as they don't use them

In any case, some of the CV joint boot flanges don't allow fitment of the plates due to their shape. I know mine doesn't. New spring washers, grease-free threads, dab of Loctite and mark it up with Tipex or similar. Then just check them every service.

Only issue we've ever had was that on the type of boots with separate boot flanges, some of the flanges were coming through too tight to fit the body of the joint properly. When you torqued up the bolts (and the torque settings as standard are surprisingly low, even for 12.9 HT spec) what was actually happening was that the bolt was pulling the flange plate inwards, but it wasn't butted up tightly internally, and that meant that once you got a few heat cycles through it there would be enough of a gap to work loose. Some of these cars had the twin-plates fitted.

Have since switched to the boots with the flange crimped to the boot, though just by adding Loctite and increasing the torque slightly the original issue was overcome.

[Blue 30]

Hi..

I have just recently removed my S3 driveshafts. First I broke x3 Torx sockets including an impact type, plus bruising around my hand when they snap.
But not being one to give up, I used my brand new shiney high quality mole grips around the bolt head, add to that another new Torx socket & bar.... Any hey presto by using 2 hands working them together, all x12 came undone. That Torx socket is now also consigned to the bin... But who cares, they're off !!
TerryB.

[zombeh]

Kitchski said:

grease-free threads, dab of Loctite

This.

If you have cv grease in the holes when you put the bolts in they can and will come undone (and then at some point when four have come out the other two will snap when you change gear)
I'm not sure how much damage the outer ones failing could cause (possibly an awful lot) but the inner ones make a bit of a mess and the grease goes everywhere and the joint doesn't appreciate being smacked into the chassis. Plus it's somewhat embarrassing slowly rolling to a halt at the side of the road.

[greymrj]

Just to update. I had one joint damaged by debris last year. I fitted a new boot but obvioulsy something got into the joint and it has started to show some play. I have just used Glen's specification advice and ordered 2 from the same company via ebay. Cost was £25.98 plus postage!!!! For both!!! That is for the full kits with boot and bolts.
I totally endorse the comments about checking bolts, I found a couple loose again on the CV which has play. I guess the extra hammering caused by the play helps loosen them. This time I will thoroughly clean the diff flange holes and locktite in the bolts and use white paint dabs for an easy visual check. I did wonder about drilling and wiring the bolts but the other 3 couplings are fine so it shouldnt be necessary.
One point (or 12 to be precise!) those 12 point torx screws are *****! They were designed for easy location of the fixing tool during manufacture, not for reuse. Because of the boot it is very difficult to get the torx screw on exactly and the screws are very easily damaged, as others have found. The original hex heads are far superior from the mechanics point of view.
Does anybody have a reliable contact for 12.9 strength hex socket head screws to fit? (my usual contact has retired)

[phillpot]

greymrj said:

Does anybody have a reliable contact for 12.9 strength hex socket head screws to fit?

There's a good little "nut 'n bolt" shop here in Redditch and I know another in Birmingham but bit far from you!


Unbrako on Ebay?

[greymrj]

phillpot said:

Unbrako on Ebay?

Thanks Mike, I remember the makers name Unbrako as on the desired spec list for a company I worked for! I will definitely follow that one up. Off to measure my spare bolts and order some from them. (I will contact you by email re the discussion you had with Debs at Burghley on Sunday)

[greymrj]

Damn, not as easy as that! The ebay shop didnt have the right size/spec. Checked with a mate and came up with a firm called; Allthread Tools & Fasteners Ltd
Fastener Supplier
Address: Owen St, Preston PR1 5DN
Phone:[phone]

Very helpful, knowledgeable and very comprehensive stock. They are sending 12 bolts to me. Assuming all is good I will make an effort to visit them soon and report back!

[TVRees]

I recently bought some bolts from here ...

http://stores.ebay.co.uk/kaysfasteners/

[greymrj]

Bought a pair from J&R using the ebay link below. Look at the price! I hope these are not being cleared at that price?
http://www.ebay.co.uk/itm/171160530021?_trksid=p20...

The units come with the gaiter, grease, circlip and tie but not with bolts.

I bought M8 x 50mm 12.9 hex socket cap screws from Allthread, 12 screws for about £5 (+P&P)! Got to be worth it to get really good bolts.

[LawrieS]

Thanks Richard, have four on order, it says 8000 and something remaining on the ebay shop, doubt they hold that many, I wonder if they make them as required. So long as the demand is there I'm sure they'll supply!

[greymrj]

Good man, sounds encouraging for the future. Dont forget; the right bolts, clean threads and loctite! We have had a few cars, including one on Eurotour, lose drive shaft couplings.

[phillpot]

And the finishing touch.......... clicky..

greymrj said:

Damn, not as easy as that! The ebay shop didnt have the right size/spec.

greymrj said:

I bought M8 x 50mm 12.9 hex socket cap screws from Allthread, 12 screws for about £5 (+P&P)!

M8 x 50mm comes up on the "Unbrako" ad on Ebay? Quite a bit more expensive .... just curious

[Jerseyjohn]

I am cleaning my drives at the momment and am thinking of some of these.
I know they are yellow but they are polyurethane, which can't be bad.

http://www.duraflexpubushes.com/cv-boots-6-c.asp

[TVRees]

Go ahead, give them a go.
Since I started working for a company manufacturing polyurethane parts, I've spent the last ten years telling everyone that PU is better than rubber. So, I'm not biased at all, honest !

[phillpot]

Jerseyjohn said:

I know they are yellow but they are polyurethane, which can't be bad.

Like a bit of colour, have you worked out which ones?