if the leak is coming from the rear main seal and not the oil pan gasket itself. You can not see the RMS and it appears the RMS is covered by the pan. So how do you know its the RMS that is leaking and not the pan itself? Mine is leaking around right now a few drops of oil per day but it drips from the bottom of the pan.

 

Does it drip if it has been sitting for a long time, or just after you have been driving?

Only drips after use = RMS

Either way, the RMS is a very common leak location on the 4.0, and the oil pan gasket is not. Since you need to do the pan gasket if you do the RMS, you might as well do the RMS (it is easy) and take care of both options. Murphy's Law states that if you only replace the pan gasket, the problem will the be RMS.

 

X2 but before you do a RMS make sure it not coming from the back of the valve cover gasket (another common leak-er) ...Tj

 

the RMS usually drips from the bell housing.
If the drips come from the starter it's the o-rings of the filter adapter
if the pan has oil around the bottom it's the cap seal or the pan gasket