CV Joints: How much slop is acceptable?

[redneck truck]

I just ordered and received a used set of OEM front axles for my A6, and I was curious - how much slop is acceptable in the inner and outer joints? Keep in mind, after I install the S6 engine parts, I may make a habit of drag racing this car.

[Vinchenzo51]

I'm of 0 help to you in regards to your original question... BUT

I may make a habit of drag racing this car.

I approve of this statement. I is excite.

[Siricospeed]

Usually None. I can understand that after using them there may be some wear in one position, however they should be virtually slop free. Take them apart and see how they are made, they should not have wear. With wear they should feel notchy when moved.

Anyone else?

[FrankA6]

I just installed brand new OEM axles in the front of my car from raxles.com

They were very very very stiff with no play or slop.

The old ones that had no rips and still visually looked great were very flimsy and loose.

The new ones made a huge difference.

[redneck truck]

Don't think I understand what you mean by stiff. It took a lot of effort to move them in normal directions? When you say the new ones made a huge difference, what do you mean? How can you tell?

[FrankA6]

Don't think I understand what you mean by stiff. It took a lot of effort to move them in normal directions? When you say the new ones made a huge difference, what do you mean? How can you tell?

The CV joints in them were stiff in the new ones and the older ones were very "limp" and "flimsy"

I was getting some noise and a tad bit of vibration in the front under load, as soon as we changed them the vibration and noise went away and now all is good.

[julex]

If you feel any considerable skipping/free play when rotating shaft while holding the CV joint, simulating how car passes torque to wheel, then the shaft has a free play and is not new. This might change with angle/depth at which the shaft sits in the cv housing too at the time of testing.

New shafts should be tight and not show any free play for many many thousands of miles.

[redneck truck]

Ok, well these were probably 100k+ mile shafts. The outers were cleaned, repacked, and rebooted, and they have no slop now, though they are not difficult to move. The inner joints show little if any free play and, though they need to be cleaned and repacked, I do not have time. The movement feels like what I could either describe as notchy or tight, not sure which. I think I'll be ok, and for the price, I'll deal. Still researching the prospect of converting to equal length front shafts to increase my options (s4 long shafts, a6 short shafts), as well as 300m 930 joints.

[Scotty@Advanced]

What do you mean slop? Slop in what range of motion?

[redneck truck]

Let's call it rotational slop. The concerning kind. Think putting a 17mm socket on a 16mm bolt head - that kind of slop. Only nowhere near that magnitude - probably 1 degree of rotation at most.

[Scotty@Advanced]

Let's call it rotational slop. The concerning kind. Think putting a 17mm socket on a 16mm bolt head - that kind of slop. Only nowhere near that magnitude - probably 1 degree of rotation at most.

Zero as in none. There should be absolutely no rotational play whatsoever.

A cheap trick is to swap cv joints from side to side. This allows them to spin backwards to the rotation they have done and the balls ride on fresh material on the opposite side of their tracks. The bad thing is you'll have noise in reverse :(.

[redneck truck]

That's a really good idea! Does that mean the wear is in the races and not in the balls themselves? This would be a lot easier if I had equal-length axle shafts and could just swap axles from side to side (see separate thread for more on this idea).

[Scotty@Advanced]

That's a really good idea! Does that mean the wear is in the races and not in the balls themselves? This would be a lot easier if I had equal-length axle shafts and could just swap axles from side to side (see separate thread for more on this idea).

Yeah wear typically occurs in the ball grooves not the balls (the balls are extremely hard). When the CV rotation are reversed the balls ride on the opposite side of the grooves.

[redneck truck]

I found some 300M inner Porsche 930 joints. Not sure if they are a direct swap. Does anyone make a tougher outer joints?

[Scotty@Advanced]

I found some 300M inner Porsche 930 joints. Not sure if they are a direct swap. Does anyone make a tougher outer joints?

Generally it's not the joints that are the problem, the axles are fairly weak. If you keep fresh grease in the joints they will last a few lifetimes.

There are tough and lighter joints out there however spending $300 per joint is not something I would imagine your too keen on doing.