I had the same thing happen with my van. The oil all over the back of the
hatch was reddish, so obviously in my case it was transmission fluid. After
a few failed attempts at different fixes, I ended up taking the transmission
to a shop in El Cajon and they did a pressure test on the torque converter
and they discovered a minor crack on one of the welds for the three bolts
holes in the torque converter. I replaced the torque converter and the
problem was solved. The difficulty in finding the cause was compounded
because the leak only occurred at higher speeds when the tranny was turning
at a high rate.

Don't know if yours is engine oil or tranny fluid though. Hope that helps
someone.

Mike