i have an oil leak on my 1999 Cherokee sport it is where the engine meets the transmission does any one know what would be the cause of this and how to fix it.
thanks

 

Sounds like a rear main seal to me. Common on XJ's, sort of a pain in the *** job, but it can be done by anyonewith a decent amount of experience/knowledge.

 

okay thanks

 

Before you think the worst. It might be only a valve cover gasket or the oil filter adapter. When those go bad the oil will also run down to the back looking like it's the rear main seal. I would clean up the engine around the valve cover and the oil filter adapter and make sure that it isn't coming from there first before ripping into the rear main seal.
BTW, Welcome to the forum.

 

WHOA!!!

See, it just happened in Post #2 as I describe it does in the following write-up.

Trust nobody but yourself in diagnosing the leak. It ain't rocket science.




　

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, 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 9-15-2012

 

My 99GC had a leak from somewhere, looked like the rms, but a closer look also revealed it was also leaking around the distributor. Not wanting to tear into it at the time, I stopped in to Advance Auto and picked up some "snake oil" Rear Main Seal Stop leak and poured it in at the store. It's been over two years since with the oil being changed every 4k and not a leak since. Not saying it'll fix anyone else's leak, but it worked for mine.

 

X2

 

Good post cruiser. I to thought my rms was leaking, it was the oil filter adapter o-rings! Check to see if the oil filter has oil on it. Also run your hand along the back of the valve cover and see if its wet.

 

I simply said "sounds like"...of course it could be something else. Knowing that isn't really rocket science either! lol. I thought my OFA was leaking..turned out the motor mount bolts had sheared off for the PO and in an attempt to fix it, he drilled one of the threaded bosses so deep it penetrated an oil passage and the oil was leaking out of the motor mount bolt hole!

Common sense says you should NEVER just replace something because someone "told you that's what the problem is" without first taking a look yourself. I didnt know a disclaimer was necessary

 

Thanks for helping me make my point though.