CV joint renewal/replacement

[bimbill]

I have had a "clunk" in my rear axle area since I got the car completed and as I checked for sources I found what feels like some play in one of the CV joints/axle splined attachment points. I have read here that the CV joints for our cars are NLA and in fact the complete axles appear to be NLA.

However, when I searched Worldpac speedial I came up with part number 33211205840 which appears to be a Porsche part that Worldpac feels will work. A reverse search of the 840 CV joint number shows it to be the E3 part. I have read here that the E3 CV joint won't work on our cars. Has anyone tried the Worldpac part on an E9? If you search the 840 part number on Pelican, it shows the same cross reference to a Porsche part number which makes sense because I think Pelican uses Worldpac to source OEM replacement parts.

If those parts won't work I will source a good used one from LJI or Coupeking. Any help is appreciated.

 

[dascoupeguy]

I just rebuilt mine. The 'play' you describe... Is it rotational or longitudinal? If I'm not mistaken there should be some play internally within the joint but not on the splines. I needed to replace the axle boots. It's a god forsaken job. The boot kits came with cv grease and new flanges. You will need a press. DCG

 

[bimbill]

Good question

DCG,

Thanks for the reply. It seemed that the play was the splines vs. balls in the cages but it is very hard to tell until everything is disassembled. In fact the more I think about it, it seems very unlikely that the splines are the source. When I searched this I found several good posts and as I recall one of them, maybe yours, said that there should be something like locktite 270 used on the splines when they are reassembled. I'll be curious to see If I find evidence of that when I disassemble mine. I wanted to repack the joints and install new boots anyway so this won't be a waste of time even if it isn't the source of the clunk.

 

[dascoupeguy]

Locktite???

Ummm ... Don't recall the locktite usage. I did not use nor did I see any evidence of its use. Just make sure the tension rings(the first to go on the shaft) are installed correctly. And make sure the snap rings are FULLY secured in the grove!!! Dcg

 

[deQuincey]

no loctite on the splines of the CV, do this,

http://www.e9coupe.com/forum/showthread.php?t=13960

the only splines you need to seal are those of the gearbox shaft, and do not use that loctite you mentioned, (270 is for bolt threads) but a sealing paste or you will never be able to disassemble it again

 

[MMercury]

Not that cv joints are impervious to wear, but I too wonder if your clunk isn't something other than a cv joint - unless you have a torn boot and permitted the joint to become contaminated or dry. (I once heard a similar complaint about another model where a mechanic insisted that the joints and rear wheel bearings were dangerously worn. When my friend went to remove a rear wheel to explore things for for himself, he found four lug nuts dangerously loose and another missing.) I am not saying this is your situation.

It might be helpful to know exactly when and from where the noise is most pronounced. Does it happen regardless of direction?

There are a number of potential noise makers other than the cv joints. I have experienced occult noises from a crack in the upper shock mounts, poorly hung exhaust, loose items near the spare tire well, failing differential mount and worn drive shaft joint - closest to the differential. Of course any noise making list should also include a differential that is worn or low on lube and fasteners for cv joints and the drive shaft. I am told that the former have a habit of becoming loose, although I am the one who has broken tools trying to remove them.

In a roundabout and noncommital answer to your cvj interchangeability question I am fearful of misleading you but I recall being somewhat lucky with a joint bought for an E3 that fit an E9. Whether this was a mistake, luck or wishful thinking, I do not recall, but the person to whom I gave it never complained after it was installed.

The easiest thing might be to actually compare the widths with a caliper. I suppose one could always measure the overall length of the half shaft (with the joints centered and attached) to determine whether alternative joints might be used. Again, I have not been confronted with this issue in some time but a simple search reveals even one Datsun owner has used e9 joints probably using this method. Whether he could have used E3 joints remains to be seen. :roll: http://www.racingonthecheap.com/wagon-irs-cv-joint-conversion/ Aside from strength, any joint used should be capable of flexing enough to accommodate the normal range of wheel movement. Thus, from a purely pragmatic standpoint I wonder whether using a slightly different width joint should result in any significant issues or functionality. But I digress.

 

[dascoupeguy]

another thing...

It might be wise to check the drive shaft to diff input shaft bolts. The PO had not fully tightened them.... quite a surprize...!

 

[bimbill]

More good points

To be clear, the noise occurs when the car is warmed up. After coming to a stop, especially with above average brake effort, the clunk is heard as you pull away. I went through all the most obvious possibilities mentioned starting with a full nut-and-bolt of everything. Again, I needed to service the CV joints anyway and because everything else back there is new, they seemed like a possible if not likely culprit. Some background: The driveshaft was rebuilt by Performance Industries; the diff is a limited slip that was rebuilt by a well regarded local shop; the diff mount is a new OE part from BMW; all the fasteners are new from Walloth & Nesch and tightened according to the blue manual specs.

I am suspicious of the diff to rear muffler clearance as I have an all stainless system based on Sven's design that requires massaging the lateral muffler for clearance. However, careful inspection shows no "witness marks" on the muffler.

I don't want to beat this to death but I will go back and recheck every nut and bolt. I hate noises that can't be identified so I'll find it eventually.

As for the CV joint, I'm going to order one and compare/measure what I find. I'll report back. Again, thanks.

 

[MMercury]

To be clear, the noise occurs when the car is warmed up. After coming to a stop, especially with above average brake effort, the clunk is heard as you pull away. I went through all the most obvious possibilities mentioned starting with a full nut-and-bolt of everything. Again, I needed to service the CV joints anyway and because everything else back there is new, they seemed like a possible if not likely culprit. Some background: The driveshaft was rebuilt by Performance Industries; the diff is a limited slip that was rebuilt by a well regarded local shop; the diff mount is a new OE part from BMW; all the fasteners are new from Walloth & Nesch and tightened according to the blue manual specs.

I am suspicious of the diff to rear muffler clearance as I have an all stainless system based on Sven's design that requires massaging the lateral muffler for clearance. However, careful inspection shows no "witness marks" on the muffler.

I don't want to beat this to death but I will go back and recheck every nut and bolt. I hate noises that can't be identified so I'll find it eventually.

As for the CV joint, I'm going to order one and compare/measure what I find. I'll report back. Again, thanks.

I mentioned the loose fasteners without knowing your obvious attention to detail, as evidenced by your photo. Given your description of the noise, when warm, could simply indicate a breakdown or lack of sufficient grease. But the more typical sound would seem to be a rythmic clicking when the joint is fully flexed. Follow a front wheel drive car with a torn boot negotiating a parking space or a tight curve.

Given your scrutiny, I would think you might be able to duplicate and exactly locate the noise with the car on a hoist. If not, you might consider removing the fasteners from one outside joint and feeling for smooth movement, followed by the next joint, and so on. Testing a dry or worn u-joint or cvjoint, with your hand/wrist, can produce a less-than-smooth, jerky, action that is fairly obvious. Of course, you could pull all of the joints at once and follow the DQ method, but it may not be necessary. And, if you locate a so-called "bad" joint, you might find it serviceable with some new grease. Try as we might, not every garage, kitchen, or driveway qualifies as a modern surgery bay.

Not to have you looking for a hayfield needle, I remember breaking the fuel pump rubber mounts on a long trip, and I would not have known about it but for the clunking it produced on a curved Interstate off-ramp. Dwelling further on the subject of undercarriage percussion, your photo shows an anti-sway bar . . .

Best of luck.

 

[dascoupeguy]

Umm... not meant to be funny...

I hate to think of something ridiculously obvious, but hey, if your looking for the needle in the haystack... Have you checked the spare tire well? And, made sure the spare tire is secured, jack secured in its proper place as well as the lug nut wrench?

You indicated that your clunk is heard after braking, and starting from a standing stop...
Could be something loose back there that moves back and forth with neg and pos G forces... Is it heard during a VERY slow start?

Hey, it would be great if it were something simple like that...! DCG

Also, after looking at your pic, I agree with MMercury as he mentiones the sway bar... you've got metal to metal attachments there....I'm sure you are using locking nuts on those!?

 

[Cornishman]

Damper top bush

I had similar noises, it turned out to be a rubber bush at the top of the damper.
Good luck
C

 

[bimbill]

Once again, I'm reminded what a great forum this is! Thank you all for you suggestions and I will be rechecking everything that has been mentioned. After years of driving and working on older BMWs I've learned to differentiate between the various little sounds one hears and the different driving conditions that produce them. This sound is similar to someone tapping the driveshaft with a hammer; that sort of hollow ring that it would make.

A note on the axle rebuild. I disassembled one axle yesterday and the first CV joint, when taken apart, looked good. No evidence of excessive heat or wear. The second one, however, showed what looked like pretty significant wear where the balls contact the hardened steel outer and inner "races". This wasn't evident on the first one so I ordered the CV joint that I mentioned in my first post, from the parts warehouse, and will measure and compare carefully to see if it is an exact replacement. As promised, I will report back.

 

[Sven]

Bill,

Another possibility are the e-brake shoes shifting. Every once in awhile when I back up I here a light clunk. I notice something similar on my V70R as well.