garry viohl Garry the rear main seal may be the problem. Is it a rope seal or Poly seal? The other problem is using RTV. I have not used Black sealer in about 10 years because of the black sealer leaks
oil in low pressure areas. The heat cycles turn it hard. There is no elestic left in it, and it starts to weep and then seap. You end up with snail trials over time. I only now use the gray RTV. This is the same stuff the Honda used in the 80's and today. Unless the motor has 100 K miles on it,
oil leaks are a thing of the past.
If you don't think the rear seal is leaken, buy a tube of the gray stuff at a GM dealership. Clean the area real good, install the part and give 24 hours to cure
You can't have any
oil dripping on this or the mounting surfaces. The other thing is to buy a leak check kit with dye for the motor. Put the dye in the motor, go for a 10-15 mile road test. Put the car up and look for a nice bright oil stain coming down from the motor. This will also save alot of guessing where the leak is coming from. I have seen rear leaks coming from the front of the motor out of the timing cover and the oil travels along the oil pan rail and leaks out the back.
Rick L.