rem did pass the time by typing:
> oil leak with the 4.0L 1990 Cherokee continually drips oil
>
> I have changed the pan ,valve cover ,distributor gaskets and the rear
> main seal the oil filter is ok as is the head gasket PCV is ok too
>
> It seems to be the oil pan or the rear main seal but the are in the
> same place -so how can I tell which is still leaking?

99% of leaks from that location are actually from the back of the valve
cover. Wipe the top of the block clean then go back after a day and check.

--
DougW