S1 XJ6 rear half shaft universal joint tolerance

Does anyone have any information on the quality and clearance of half shaft UJs. I have rear wheel free play, feels like bearing freeplay but is movement in UJs (both on each shaft) which are not that old. When fitted still had movement that equated to WOF time concerns by the inspectors. With the comment, “will let it pass this time, but needs to be looked at”

Hi Damian. Taking a stab here but are you in NZ? (WoF reference)
There are different qualities of UJ joints, sounds like you were supplied ones with a looser tolerance.

Only bearing play is given and adjustable, Damian…

The set-up relies on ‘no-play’ driveshaft connection between hub and diff to maintain correct bearing play. Play in UJs (or somewhere on the driveshaft) will, as you observe, increase measured bearing play…

In short; there should be no pay in the UJs - and Robin may well be righty; poor quality. Or unexplained wear…

xj6 85 Sov Europe (UK/NZ)

there was a thread on that recently, with pics,
the thread starter setup his dial gauge and stated new UJ should in fact have
a small amount of freeplay, iirc it was .001"

This doesn’t sound right to me but I’ll admit that I’ve never researched it…or even given it any thought. I’m willing to learn something new. It’s a new day, after all!

I’ve always considered u-joints to be “no free play” things. But .001" is very slight. It could very well be the norm and I’ve simply never noticed…and certainly never measured. In the field, so to speak, you’d have to go out of your way to check for .001" free play. And .001" makes sense from a manufacturing and longevity standpoint, it seems.

Any free play that it palpable or visual while gently levering the shaft or joint is clearly unacceptable. An old u-joint in this condition has probably lost its lubrication and/or been contaminated with water and dirt. And, even allowing for varying quality levels, a new-ish u-joint in this condition was probably incorrectly installed or never greased to begin with. I’ve bollixed up a few in my time.


Considering there are 8 bearings in the U/J’s its only going to take one of them to have a slight amount of wear/free play to start showing up at the wheel extremities.

It didnt sound right to me, given I have found fitting new ones are sometimes too tight,
and it was within that context that his pictorial, and commentary was quite convincing

I will endeavour to locate that thread, and see if Google search sheds any light on that matter,
and edit the results back in, so i can learn more

In any case, imo, their should never be any freeplay in a uni joint that is “detetectable” in situ.
<.001" would be such, but I have to find the thread first

I have found that the u joints I installed in my 63 e fhc half shaft have excessive end float. This wasn’t apparent to me when I installed, but after driving for a few years, summer only, that there was a clicking sound. Sure enough end float on the outer joints. Oddly enough the inner do not seem to have any.

It seems to me that some free play mut exist. were there noe, the bearings would be solid and have no movemtn that alows them to function. How much, I dunno. having an issue with visualizing .oo1!!!

End float is different, I think. There’s the question of how snugly the cross fits into the four roller bearings, and I’m with others on that, my impression has always been no play at all, new ones seem a little snug when first assembled.

End float would be the clearance between the ends of the cross and the bottoms of the bearing cups. Those bearing caps are pressed in and then held with clips. As I understand it, those clips are stamped from sheet steel and are supposed to be installed with the flat side against the bearing cup and the side with slightly rounded edges – from the stamping process – facing outward so that it wedges itself into the groove. Sometimes the grooves are cut with a slight taper on the outside edge to facilitate that. When installed properly, I don’t think they should have any end float.

Carl, if you have any hair left just pull out a strand or if you remember ZIG ZAG cigarette papers they are .0005” thick and the hair is about .002” from memory.

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Did you check the endfloat, and inspected the joints with the driveshafts in or out of the car, Robert?

And if you have been driving ‘a few years’ - this may be caused by wear and/or lack of proper lubrication, or some hick-up during replacement…?

xj6 85 Sov Europe (UK/NZ)

Good questions. By a few years really about 12, but I would guess no more than 500 miles per year. As to the fit, when I installed them everything seemed correct i.e. I didn’t sense end float, but in retrospect it must have been because I did hear some clicking. Thought it was something else.
Just got a lift in my garage so did some checking on things and this is when I found the end float. New Spicer u joints on order. We will see how they fit


I do have a good deal of hair. thining, oh yeah.

I have not touched a ZIG ZAG paper since my college days. Some of us rolled our own. Cheaper than tailor mades!!!

Origin unknown. I do have a sack that may have contained Bull Durham tabaco. Hangs on my garage wall.

I recall an engineer friend referring to a measurement. RBH. full name not printable.

But, I get the scale. Thanks.

Carl .

There is little to no rotational play in a good u-joint providing all of the roller bearings are lined up like skinny soldiers against the cap, and didn’t fall out during the installation. If the bearings have gone missing then there will be play and vibration like a tyre put of balance when driving

When you say Wheel play are you referring to rotational play or lateral play? When you performed the test. Did you do it with the handbreak on? The reason why i ask is if you get rotational play with the hand brake on which would isolate the ujoints down to the carrier hub, the only play would be either the splined shaft in the carrier hub and the ujoints.
If a touch of loctite wasnt appled to the splined shaft when inserted into the wheel hub there can be a little clunk where the splines are essentially bouncing off each other. Durning initial acceleration and deceleration.

Lateral play is bearing or the improper sized spacer bwtween the inner grease seal ring and the back of the inner wheel bearing

If the test was performed with the hand brake off, then it could ne anything between the wheel hub and the differential.

Worn or damaged u joints will display lateral movement at the joint and not at the wheel hub.

Im pretty sure the OE u joint was a spicer brand ujoint any quality part like the OE or timken, or smc, dana, a good inexpensive alternate is GB which are a Japanese bearing Company.

If im missong something chances are someone will point it out.
On my YouTube channel i show pressing in u joint s. Im not a fan of beating them in this where your more likely to break or lose a needle bearing. That’s been my experience anyway.