Here is how Audi modified the half-shaft (driveshafts). The inner joint and boot appear to be stock Audi Quattro. There are some differences on how Audi mounted the Inner CV joint housing to the differential flange. Instead of the six internal 12pt. bolts that normally connect the urquattro halfshaft to the differential flange, the setup includes just 3 bolts which are 12pt external stretch bolts and 3 centering pins. The rear CV boot still covers the CV joint itself and is held in place via these 3 bolts. Since I have the shafts off the car, its a good time to clear, repack the Joints and replace the boots. Here is a picture of the inside face of the inner CV joint (the face that mounts to the differential). You can see the 3 centering pins. I guess Audi did this for speed of replacement.
The outer CV joint appears to be very different than stock urquattro. The most notable visible differences is this band of latex sealant that runs around the entire housing. The spline receives a bolt for the hub rather than a nut.
Here is the original outer CV boot. Notice the smaller large diameter and see the shoulder upon which it clamps. This is actually an outer Boot. There is a seperate inner Boot that can be seen in the picture.
Here is the inner boot. It appears to be clamped by the steel cover assembly and held to the shaft by the standard CV band clamp. The inner boot has a tear on it. My suspicion is that Audi devised this setup because of boot failures from the gravel.
A good shot of the single roll internal rubber boot.
I peeled off the latex sealant that was applied to the axle. It appears that this is hybrid cover spot welded onto a modified factory outer CV joint. If I had to guess its integral to the internal boot. The grease that I saw on the inside of my wheel was coming from a tear in this latex sealant. I'll clean and degrease the steel and use a more modern sealant than latex caulk. But it looks like I might have to replace inner boot. The joint is in good condition so I could install a new outer boot and it'll work fine, but I might as well try to find out if this part is available from some other car.
A stock urquattro outer boot cover versus the one on my car which is smaller. If anyone can identify the one on the right, let me know.