When rotating the right axle by the wheel or hub, there is a small spot in the same place of most every rotation where there is more resistance. When I keep turning through the resistance, there then comes a quick release of the resistance and at the same time a dull single knock sound from the axle area. I am thinking bad CV or wheel bearing, but am a little hesitant because the PO replaced all 4 CVs and the wheel bearings just 20K miles ago...though the car did some hard AutoX.

The caliper is not mounted and the transmission is in neutral. I do not hear anything when driving, except a similar knocking from the right rear of the car when starting from a stop on a hard left uphill turn onto level ground.

On closer inspection, there are 3 spots in each rotation where there is resistance and a dull clunk - they appear to be evenly spaced around the 360 degrees. Seeming more and more like a bad CV...but none of the boots have any tears.

You have a 40+ year old car. Unless you know that all of the CV joints have been replaced you have to suspect they are worn. So plan on replacing and the rear wheel bearings as well.

Yes! What he says, and explain how this is “kinky.” Oh, and remember, the Garage is rated PG.

I lost my CV joint going uphill at 70. I thought it was the motor. Check the whole assembly...

New OEM axle and CV assemblies are actually avail from Porsche. Last time I bought a set I think they were about 250 each...

The resistance feels like a "kink" in the hub or axle when it's turning.

I don't feel much play in the CVs. Any chance this could be in the transmission?

With it happening in neutral, I thought not, but don't know enough to rule that out for sure.

Yeah, they are still listed...$270 each.

PCA discount?

The CV's don't really rotate, they articulate, flex up and down, in and out. If you have the car on jack stands at full droop. When you rotate the tire attached to the disk (no caliper) you really only feel the rear wheel bearing and the e brakes bragging ................

You might what to check the torque on the inner CV joints. It could be wobbling around and about ready to fall off/out. Not Good .............. Out of sight, out of mind.

As a basic rule. CV joints clunk. Bearing drown.

When I removed my driveshafts I found a distinct clunkiness in each of them at particular points in their rotation. On dismantling the joints I found discrete and distinct indentations in the bearing surfaces in a number of places on every joint. Hopefully the picture shows this. I replaced all the CV's.

The replacement deal from Porsche is a bargain! By the time I cleaned up, dismantled, cleaned some more, painted the driveshafts and re-ssembled I had expended a whole bunch of effort for more than half the cost of complete driveshafts! Pay the money!Click to view attachment

Here is what I do with good results. Get a tube of cv joint or moly grease and put it in your grease gun. Remove the zerk fitting end from the grease gun and screw on a 1/8 inch female npt to 1/8 inch compression fitting. Put a 6 inch long piece of 1/8 inch plastic tubing into the compression fitting. Then remove the small clamp on the CV joint boot and shove the tubing into the boot between the axle shaft and the boot all the way to the CV joint and pump in the grease. One tube of grease will do all four CV joints. I remove the tubing and reinsert 120 degrees around giving each CV grease in three locations. I then use a heavy duty tie wrap as a clamp on the CV joint boot as a replacement for the SS clamp. They work well on the axle side.

If the boots are torn, well that’s another story. I have refurbished Mercedes axles with new boots and cleaning and regreasing the CV joints.

Charlie

Re your question of if this is a transmission issue, if not both sides doing it, then no. The diff can spin, will spin the pinion, but if in neutral then the gears inside are freewheeling. If shifting Ok and not making any noise, you an rule the transmission out. CV and bearing are correct suspects. If you detach the CV from the wheel end, you can fairly quickly determine if the wheel bearing is bad as you will then have isolated it. And then you can also clean/inspect/lube the CV.

While it is overkill. Tarett Racing has an upgraded set that I think comes from one of the V8 conversion companies that are a bit more expensive but will likely stand up to anything.

I know the stock ones can take a lot more than I give them credit for but I have just had a number of issues with the replacements and I just wanted to over do it and be done. The stock ones are fine and would recommend following that path over replacing individual ones.

The deal even gets better if your paying someone to do it ........

I don't want to hijack, but does anyone know why CV joints are NLA if you can still get them on complete axle assemblies? Why are we having to mod Type I joints to rebuild our own axles?

Thanks for all the information and experience on inspecting and maintaining the CVs! I'll remove, inspect, rotate the hub without the axle to diagnose the wheel bearing alone, relube and retorque the CV, and then report back on what I find.

Great question bbrock - seems like Porsche would want to sell just the joints separately from the axle assembly...Or, maybe that's intentional ($)...

Thanks for the explanation and suggestion! This is a big relief!!

I had what you’re describing on one of my cars. A new wheel bearing fixed it.

Pulled these out of the scrap barrel. This is what you DON'T want to see inside your
CV joints if and when you get there. You can feel the scar with your finger nail.
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Click to view attachment