I seem to have acquired what looks to be a rear main seal leak, a leak some where higher up wetting the oil pan, maybe a leaky pcv or ccv (can never remember what they are called) and there's always a little oil on the filter that looks like it's about to drop. Sometimes when I have gone on long highway drives oil comes from somewhere and drops on the exhaust causing smoke (only under load) and I just want to see what ya'll think. Sorry for all the questions and maybe wrong terminology but I'm not a seal expert and hate leaks. If there is another thread or write ups that have been posted and sound like one or more of my problems please post link. I've been trying to figure them out but the only one that seems common is the rear main seal and I think I'm going to try and tackle that next oil change. The app isn't letting me upload photos so I will try again soon. Thanks in advance!

 

Photos

 

This looks like mine if you don't have any crakes in the pan id say its the gasket.

 

Check valve cover gasket and oil filter adapter O-rings, those are a couple of the biggest oil leak areas

 

Just replace the valve cover gasket

 

I don't see any cracks in the pan. I guess when I do the rear main seal I'll check the pan and I'll be redoing the pan gasket anyway.

 

Definitely need to check that oil filter adapter for leaks. Those o-rings inside dry out and leak over time. If you let it go long enough it will leak like CRAZY! Getting the oil filter adapter off can be a little bit of a pain, but the replacement o-rings are cheap. Not to mention that having no more oil leak is really nice.

 

Yeah looks like that's definitely on the list just gotta get all the seals together and get all the tools together and I guess maybe just have a whole day of oil leak fixes haha

 

Oil filter adapter leaking will make it look like your rear main seal is leaking after you drive. Be sure to get the O-rings from the dealership. Maybe $4 I think is what I paid. They had to overnight them from another store so I got them the next day

 

I would look at the adapter as well. in the pics you can see that oil filter has oil on it most likely from the adapter. I would also look at the oil pressure sending unit an make sure that elbow on there is not leaking as well.

 

Yep. Just about any leak will look like an RMS leak. That's where it collects and drips.

Start at the top and work down. Valve cover gasket, then the oil filter o-rings.

Then clean it up and re-evaluate. You may NOT have an RMS leak.


If you do, consider trying this stuff. It's worked very well for me on my power steering and on a front main seal on another vehicle. Both were really bad leaks. Took about a week of daily use for it to take effect, but it stopped both leaks. It failed to stop a transmission leak, so it's not fool-proof, but for the price, it's worth a try.

 

I recently replace the oil pressure sending unit and i don't believe it is leaking.

 

Valve cover was recently replaced so oil adapter is next. I don't really like the idea of any kind of stop leak personally. Id rather just do the seals.

 

Good luck, that's one of the worst things to diagnose. Mine leaked from the oil adapter, looked similar to that. But really hard to tell.

 

I wrote this:




I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.

Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.

Many mechanics, friends, people on Jeep forums who can’t see your Jeep from where they’re at, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?

A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.

First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.

Revised 02-26-2013