I have an oil leak coming from the rear of my '04 4.0. Before I pull the transmission to fix whatever it is, where are some common oil leaks at the rear of the 4.0 SOHC?

 

Take a look at your valve covers first. With age the seals get hard and don't seal as well. They can leak down the side and back to make it look like a leak at the rear. I had to replace my right side valve cover seal and the left will probably need it before too long.

 

I think I have found the culprit and it isn't the rear of the motor at all.

There is a good size bolt going into the head above the passenger rear spark plug. I think this is the source of the leak. I assume this is something for the cam chains.

Is there a gasket or copper washer that goes on this bolt?

 

The oil leak is definitely coming from the passenger timing chain tensioner. I'm going to see what the tensioner cost from the dealership and see what a local shop would charge to fix it.