4.0 oil filter leak, best fix?

So I decided to replace the battery cables today on my '96 (old ones were okay, but seemed a bit too long for my liking... FWIW, a 32" ground cable is just about the perfect length and a 25" positive cable is about an inch short on a 4.0 lol) While I was putting the engine block bolt for the ground cable in, I noticed that yep, I had a bit of pretty fresh looking oil on my oil filter. I know that this is no fault of mine or the oil filter (it's a K&N, I lubed the seal before I put it on, and tightened it not a lot, but a bit more than I should have.) It's not a huge leak, if I keep an eye on the oil level it should be fine until the next oil change, but I still don't like it... Right now I'm suspecting it's a bad oil filter mount or seal in there, which sounds like a pretty common problem. My question is what, in your guys opinion, is the best way to solve this problem? Just a new seal/oil filter mount? Oil filter relocation kit? (I'm thinking something that places the oil filter in an easier-to-reach location without the possibility of leaking oil all the starter would be pretty nice...)

I would be sure of the source of the leak before buying parts. The oil filter mount is held to the block with a large bolt and that bolt has a few o-rings and they are notorious for going bad. This causes an oil leak that hits the starter and continues running downhill until it drips off the bottom of the bell housing.

New O-rings for the filter mount.

Make sure you get all of the old o-rings out. I recently pulled a motor, to find 2 o-rings doubled up, ::facepalm::

V-hunter said:

http://www.amazon.com/Jeep-J-Series-Cherokee-Filter-Adapter/dp/B00B9OR1ZS

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Cheaper at the dealer.

T60 bit with adapter. To free your oil filter adapter, combination bolt.:arrowl:

Okay, thanks guys. Like I said, it's not a bad leak, from what I saw, the military would classify it as a class 1 leak (the most minor of the the 3 classes.) And considering that I just paid $50 to change the oil myself with the good stuff, it can wait until the next oil change to get fixed. I've been holding off on degreasing and pressure washing the engine bay just because the engine bay seems to be missing some parts that help keep water from getting into where it doesn't belong (like a little square piece for the bottom of the intake box), but doing that would definitely help identify where leaks are coming from and the engine bay and underside desperately needs it.

Think of it as old-skool rust proofing.

The biggest problem with changing the o-rings is usually figuring out the way to get the T60 bolt out. Its very close to the unibody rail so a ratchet or breaker bar won't fit. Some buy a T60 socket and beat it out to use the bit with a wrench and a cheater bar. Others get a T60 allen. I used the T60 socket with a serpentine belt tensioner tool which is basically a long bar with a 3/8" square drive head at the end. Its thin enough that it works if you go at it from the bottom. Then just add 1 quart of oil or whatever your filter takes.

Hypoid said:

Think of it as old-skool rust proofing.

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Haha. Yeah, not too much of a problem in my neck of the woods, the paint and clearcoat on this thing is pretty faded from all the sun.

As a side note, the cottonwood trees in my neck of the woods are looking absolutely GORGEOUS.I might have to go out and take some good pictures with an actual camera, but it's the goldest gold you can imagine... like something in a Van Gogh painting. Unfortunately, these cottonwoods only grow along the river bottom areas (where they can get enough water.) Everything else? Yep, brown and shitty and dry-looking. That being said, these beautiful cottonwoods have me longing for my homeland of eastern Nebraska (where the state tree is the cottonwood) and all the fun fall-time activities. :'( Sorry, but screw mountains, give me corn mazes and hay-rack rides and bonfires and kids leaping into leaf piles and grandpa throwing a pair of apple-picking grandkids into the tractor bucket lol.

Here's what you do:




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
And there are write-ups around for doing the OFA seals.

I'm pretty good at running down leaks, especially slow "Class 1" leaks (wet/dirty, but not forming droplets) My rule of thumb has always been "up and forward" and it has served me well. Case in point, the old man had me go over his F350 when he bought it. Everything looked great on that truck, but I found what I thought was a leaky rear diff seal. Using the "up and forward" rule I was able to trace it the pinion area.

My oil pressure sensor housing area looks dry, rest of the passenger side of the engine bay definitely needs a good degreasing along with the underside, but like I said, I'm still a bit leary about water getting into where it doesn't belong at this point. Right now, I'm seeing fresh oil on the bottom of an otherwise pristine, white oil filter. Oil filter adapter seals is my first guess, although judging by the care this thing seems to have received, I'd be willing to bet some other gaskets and seals are bad too.

I like the "up and forward" term and method.

I have pondered this for years. I finally changed out the o-rings last week. The undercarriage is now bone-dry.

Best solutions: use OEM kit, not aftermarket. The only exception is Viton rings, if you can find them. Torx Allen wrenches work best. Removal from the top is easy. Use a floor jack handle slipped over the T-60 for easy removal. Change every 3 years and you will never have to put up with an oily mess again.