2Evil4U

I always loosen all of the main cap bolts when I'm doing the top part of a two piece seal.

maxxtreme

i followed the steps of the link, and it took me 4 hours to take out the upper part of the seal!!!!, it was so tight that i was worried all the time for the crankshaft, at the end, it was so difficult also to replace the new one, i am just wondering if i missed something, or if i did anything wrong..., the point is,... it was hard like hell to replace the seal, maybe it was the original part,´cause i checked the bearings and it was in an incredible shape for been the original (never changed!!)...did anyone have the same problem changing those seals????

udownwitk

Great info in here. I just replaced the valve cover gasket and I still have a teardrop leak at the very bottom of the motor. Might have to change my seal.

racebum

he was correct. there should be little if any difference in pressure between a new and used pump provided the used pump is functioning correctly.

also oil leaks are caused by hard gaskets and or excessive crankcase pressure. an oil pump will have no bearing on if you do or do not leak oil

RGibbs

I don't mean to hijack but I think mine leaks to but only when I pull my band trailer. Has anybody had a leak when pulling?

DFlintstone

I admit I only skimmed over this thread.

A leaking oil filter adapter can look just like a rear main leaking, the oil blows around. To see you might clean things well, then watch closely. (a rear main might leak if the crank moved over a tad).. I like this one, clicking on the pics expands them...>>>

http://www.myjeepxj.com/cherokee-rep...filter-adapter

Chonson

Did some digging and this thread seemed like a good place to post my question. I was told by a jeep mechanic that changing the rear main seal on a high mileage cherokee has a 50/50 success rate. He explained that the old seals harden and overtime, create a groove in the metal. This will cause a new seal to fail as well and possibly make things worse.

How true is this statement because I know for a fact my rear main seal and oil pan gasket are busted and with 153k on the motor I'm worried my XJ might be close to demise.

He also quoted me $500 to replace rear main and oil pan gasket. Im thinking oil pan gasket is easy to change whereas the rear main would be more difficult. Ive done valve cover, oil filter O ring, and tranny pan myself so I might give this a go if replacing my rear main doesn't have a 50% chance of making things worse. I appreciate the help.

DFlintstone

All I can say is 150K is not really high for the 4.0. One of mine is fine, strong and healthy at over 280K, and another just went past 200K. Nether has much blow-by, both get over 20 on the highway. The one at 200....I suspect it's rear main is leaking because someone botched the replacement when it needed oil filter adapter O rings.

Do be sure the large 1/2 inch tube from the valve cover to the air cleaner is free and un restricted. People do goofy things...an aftermarket filter or a smaller tube can cause crank-case pressure that will make it blow oil out where it can. RM, front seal, dizzy and or the dipstick/valve cover.

My parts are sitting here waiting, I haven't done a RM on a 4.0, but soon. I intend to disconnect the shocks and let the front axle hang, and unbolting only the rear bearing cap, use a drinking straw and dish soap to feed the new seal in without boogieing it up.....

Chonson

Yes I certainly hope my XJ is only halfway through its lifespan. But if the rear main has the groove like I was told about Idk what more can be done. I asked him about an expanding foam type seal and he told me he doesnt believe there is anything like that for a RM. Some of the other aftermarket gaskets are made for older worn out vehicles but not the RM.

Im a bit worried to attempt the RM in the first place and now that I know about the possibility of this issue I dont think I will attempt to change it. The straw dishsoap method sounds wonderful too bad you dont live near me There used to be a few drops of oil on the pavement directly under the front of the motor below the largest pully that holds the serp belt but i think thats from the oil pan gasket. Aside from that shes stopped dripping on her own and the oil level is always good. im going to clean it up nice and inspect the rear main. Hopefully all the mess is from the oil pan gasket and making its way back.That would be my saving grace.

At what point in time does a rear main usually go? Is it possible an OE rear main can last well past 150k miles?

Edit: I changed the rubber sleeve on the 1/2 tube from valve cover to air box bc the old one was cracked. I also changed the elbow and grommet on the front and back of valve cover... Hope that didnt cause any harm hmm but it seems like that area is all sound no oil in air box and tight seals.

gvnc

universal joint sockets. I have the precats on my '01 and had no problem with the swivel and some extensions

DFlintstone

A couple of years ago I bought a pan gasket and RM for "Brown" the one pushen 300K. Turned out there was a kink in the tube I had venting the VC, so I returned the parts I'd bought.

I live in the sticks where it's all dirt and gravel. Back when I waz working some, I'd carry a piece of cardboard for if I needed to park on someones pristine, clean concrete driveway. It drips very little, but sometimes even that is not welcome. It needs less than a Qt per 1000 miles, so there is that. I have no intention of going after every little drip.

"White" on the other hand is pissen, and it gets on the exhaust crossover. When I hit my hill coming home, (1,500 foot climb in 3 miles), that pipe gets hot and I leave a cloud of smoke. The Castriol I use is about $5 a quart and it's leaking around a quart/tank. Getting on that soon..weather is now OK but I'm loaning Brown to a neighbor, so no spare wheels for a town trip.

md21722

I hear some stories where replacing the RMS does not fix the leak and others who say it'll come back in a year. I've done the RMS on each of my XJ's. I did the 97 XJ at about 197,000 miles a year ago and its been leak free. I just did the 01 XJ at 340,000 miles and its still dry. If the crank is not worn then it will probably hold just fine. Some tips & suggestions:

1. I used the drinking straw & soap on the back of the seal and oil on the lip technique.

2. Use a BRASS PUNCH to drive out the upper seal. Yes, the brass punches may bend, but you can straighten them out. Its far cheaper to use a brass punch than accidentally gouge your crankshaft.

3. For the pan gasket, RTV is needed in 4-6 locations. I put it at the bends around the front cover and rear bearing cap, and also where the block meets the front cover.

4. Use studs to hold the oil pan gasket in place against the block and press it into place around the rear main cap. Then you just put the pan over the studs and start installing bolts working from center out.

5. Torque spec is 84 in-lbs for the smaller bolts and 132 in-lbs for the larger ones.

6. Consider using Vibra-tite or some other means of holding the bolts from vibrating loose. I hear weathering stripping adhesive also works. There is probably something in your toolbox that will help. The only leak I had on my 97 XJ was from the front cover bolts backing out. Adding Vibra-tite solved that problem.

7. Rear main bearing cap and block surface get small dabs of anaerobic sealer. Its red and perfectly suitable for applying directly to the block and cap. Check the FSM for more information.

8. On a stock XJ, I strongly suggest removing the sway bar at the body side, track bar from the frame, and steering dampener from the drag link. Then jack up the body and let the axle droop low. There will be enough room. Shocks should not need to be disconnected but can be if needed. If your XJ is lifted you may not need to do all of these things.

gvnc,

Glad the universal sockets are working out for you.

DFlintsone,

I'd suggest getting in there in doing it.

Chonson,

I don't know how frequently they go. My 01 XJ started weeping around 160-180,000. I've heard of them leaking as early as 75,000. I decided to change the cats when I had all of this apart on my 01 XJ. If the cats are touching the oil pan then they were probably whacked at some point. You should be able to slip your finger between the cat pipe and the oil pan. That was part of my problem. The cat pipes were resting on the oil pan so I couldn't get to the oil pan bolts. As far as the cats, that's where the universal sockets come in. For the 4 flange bolts up near the manifold.

dpetro1

great tips. in relation to #8, the FSM says to unbolt the engine mounts and raise the engine for clearance supporting the crank pulley with a jack stand. anyone have success doing it that way?

stump1

So I recently replace the oil pump and screen and the oil pan gasket and I didn't get to do the rear main seal so my question is do i have to replace the oil pan gasket again if I re-drop it to replace rear main maybe have a 100 miles on it since new gasket

LiamLikeNeeson

You have a Jeep that leaks oil? Same. actually. Don't we all have a Jeep that leaks oil? Lol. Anyways I will be doing the rear main seal, VC gasket because it's leaking all around and oil pan gasket and moving over to good ol Rotella. I have an 89 Jeep and was wondering if it might not be a bad idea to pick the valve cover off of a 91+ XJ because it uses grommets and I should have less chance of incorrectly mounting the VC and springing another leak which I heard isn't too hard to do on Renix valve covers. I also believe it has a bit more clearance on the inside. Has anyone done that swap?