Originally Posted By: sicko
Any chance she drove through some oil/dirt/grime and got it on the tires?
The oil pan, transmission pan, and differentials, are all pretty much straight down the center, so it's unlikely oil from any one of those drain bolts is causing the oil spots near the wheels.
How about the brake lines? Did you recently bleed the brakes, are you sure that the bleeder valves are properly closed?
Rub some of this stuff between your fingers and see what it feels like.
Smell it and see whether it smells like ATF, brake fluid, coolant or motor oil. The CV joint grease is a medium dark grey high moly compound that does not have a liquid consistency.
I think you're right and that the OP's wife probably drove through something.
I can't imagine that you could lose enough brake fluid, ATF, coolant or engine oil to leave stains on the ground at all four corners without the source being pretty obvious.