DLO4200

so I just had my oil pan gasket and rear main seal replaced on my 99 4.0. also my oil filter housing adapter gasket replaced ...ITS STILL LEAKING !😲😲when get. under the jeep it looks. to be. coming from between my bell housing and my inspection plate ..any ideas on where the oil is coming from .thanks

cruiser54

Could very well be the valve cover bolts are loose along the back. Grab a 7/16 socket and check it out. It's common. That's why I wrote this years ago:


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: “Crap 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.

DLO4200

ok check those bolts thanks a lot I feel like I have been chasing this oil leak very where in the last two weeks

cruiser54

Yeah, I know. That's why I suggest the Jeep owner do the diagnosis themselves.