Where can oil/grease come from on the CV boot?

[briwayjones]

The right front on my 2000 for a while has been sounding like the bearing is going out. While replacing the brakes on it recently I checked it for wheel play and could find no discernible play. I did notice that there is oil/grease on one rib of the CV boot that is getting slung around in there and on the fender skirt. I couldn't figure out where it was coming from. I couldn't find any cracks in the CV boot, there's no oil in there anyway is there? Any ideas?

 

[2TimingTom]

It's probably a cracked CV boot. It doesn't take much of a crack when you're driving 70 mph for the grease to find a tiny hole and fly out.

 

[OneLever]

At any location the boot is torn. The CV-joint is packed full of grease to lubricate the bearing. Clean off the boot and go for a "spirited" test drive. See if more grease has appeared in the same spot. If so the boot is probably torn.

If it is to the point of making noises the CV-joint bearings are likely shot and you will have to replace the CV-joint. On most years the joint is integrated into the halfshaft (aka drive axle) so you have to replace the whole thing. Barring that the best thing you can do to buy time is rebuild it which takes more effort than putting in a new halfshaft.

See this thread and this thread for more info. Props to Turdle for the awesome rebuild tutorial.