rear main seal, how bad is it really?

[SonicCougar99]

My rear main seal on my 89 XJ Remix has been leaking for quite some time, but lately it has worsened pretty badly, to the tune of a quart a week. I don't consider myself an idiot when it comes to working on vehicles, but I'm far from an expert either. How hard is it to change this thing myself? I would love to just have someone do it, but I'm not not sure my finances will allow that. I did a search (albeit from my phone) and couldn't find any write-ups on it to get an idea on what I'm looking at. Thanks guys, I very much appreciate it.

 

[MoabXJeeper]

I did mine last year in my 92, it honestly wasn't that bad. Just really time consuming. My first suggestion would be to get the most comfortable creeper you can get your hands on, you will be spending HOURS on your back! Also, it's a good idea to go to a pressure washer and spray off the underside of your Jeep so crap doesn't fall in your eyes while you're working.

Here's a really good series of videos I watched when I did mine:
http://www.youtube.com/watch?v=ft4LhJWOgtk

Good luck man

 

[garr]

Easy for an average mechanic,
One tip, Drain the oil & remove the pan late afternoon,Let it sit overnight to allow all the oil to drip out, The next morning when you get to work on it you will be very happy that No oil is dripping into your face!

 

[iwannadie]

Don't try to cut any corners, remove everything and get that front axle to drop as far as you can. No sense in leaving something connected to "save" time and then fighting with the pan. It's no fun laying on your back banging around a dirty oil pan, if it doesn't fall right out go and disconnect something and get the axle to drop more until the pan falls out.

 

[saki669]

I tried it twice and it still leaked. I finally gave up and had a local shop do it. $400. Well worth the cash to have them handle it. I've done plenty of outside engine work and general mechanical repairs but the rear main seal was just a nasty messy job. I probably spent a good 8-10 hours on the creeper. Good luck.

 

[xcm]

I pull the front axle completely out of the way. Detach the brake calipers and hang em, then unbolt and roll out the front axle. Gives you breathing room. That, or do the rear main on an engine stand. Much much easier.

Make sure you have a brass punch, and make sure that brass punch is the right size and placed right to punch out the old seal. Ive had issues before, where ive had to loosen the crank caps, to allow the rear of the crank to move around a 1/4 inch or so.

 

[cruiser54]

Are you sure it's the RMS leaking?

Don't jump on the RMS/oil pan gasket bandwagon right off the bat.
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

 

[ParadiseXJ]

I tried it twice and it still leaked. I finally gave up and had a local shop do it. $400. Well worth the cash to have them handle it. I've done plenty of outside engine work and general mechanical repairs but the rear main seal was just a nasty messy job. I probably spent a good 8-10 hours on the creeper. Good luck.

I was quoted $600...I don't make $600 in an 8 hour shift...it only took me 4 hours. Mostly dropping the pan (and removing a good chunk of the suspension). The seal itself...5 minutes. It's not worth it to me to pay ANYONE $100 an hour to do anything with their clothes on.

I pull the front axle completely out of the way. Detach the brake calipers and hang em, then unbolt and roll out the front axle. Gives you breathing room. That, or do the rear main on an engine stand. Much much easier.

Of course it would be easier on a stand or with the whole underside removed, but it's not necessary. Maybe a bit extreme...pulling the engine or removing the axle, that is. The job can be done just detaching a few things and dropping the pan...ba-da-bing.

Are you sure it's the RMS leaking?

"$hit flows downhill"

THAT is true!! In everyday life.

 

[SonicCougar99]

Are you sure it's the RMS leaking?

Don't jump on the RMS/oil pan gasket bandwagon right off the bat.
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

I've already addressed the valve cover gasket and it doesn't appear to be coming from up top anymore. I'd love to find a steam cleaner and spray the engine bay and underside all off and see what's coming from where, though.

 

[cruiser54]

I've already addressed the valve cover gasket and it doesn't appear to be coming from up top anymore. I'd love to find a steam cleaner and spray the engine bay and underside all off and see what's coming from where, though.

That's what I'd be doing for the exact reasons I covered in my post.

 

[bigalpha]

I got a long, brass rod from Ace Hardware to help punch the old RMS out. I think it was easier than using a traditional brass punch since it was much thinner and longer. It was easier to get in a good position.

 

[SonicCougar99]

Any idea on what sort of ballpark I would be looking at for having a shop do this? I really don't see where I will have the time or patience to tackle this.

 

[EXJAY01]

Any idea on what sort of ballpark I would be looking at for having a shop do this? I really don't see where I will have the time or patience to tackle this.

Well the 2 people above said they were quoted at 400 and 600 so probably some where around there.

 

[SonicCougar99]

Well the 2 people above said they were quoted at 400 and 600 so probably some where around there.

DOH! Not sure how I missed that.

 

[magimerlin]

I'd check the Arizona chapter and see if one of the members in your area can give ya a hand befor bringing it to a shop. Friends work much cheaper and the good ones work for beer and pizza.......lol. A wrench-a-thon is a great way to meet more people in your chapter to.

 

[djlarroc]

I was quoted $600...I don't make $600 in an 8 hour shift...it only took me 4 hours. Mostly dropping the pan (and removing a good chunk of the suspension). The seal itself...5 minutes. It's not worth it to me to pay ANYONE $100 an hour to do anything with their clothes on.

lmao.

i did the rear main on my '95. if you dont have a lift (kit), it's even more of a PITA. my jeep did, and it still took a buddy and i about 5 hours.

 

[xcm]

Worth and value are relative. People pay for oil changes every day...

Oh, and shop time > your time. Its just a fact. Your buddy wont do it over again for free if it leaks, Your buddy doesnt run a commercial buisness.

 

[MoparManiac]

If you do it yourself, make sure to get the one piece oil pan rubber/metal gasket.

Not worth the hassle of dealing with the cork gasket.

 

[SonicCougar99]

Got a quote from a decent shop for $340 for the rear main, oil pan gasket, oil, and filter. Much better than I was expecting, so that's what is going to happen at my next paycheck. Thanks for the advice guys, this is just more that I really want to deal with right now on my own.

 

[mako my day]

That's a great price. Do it! My local guys charge about 430.
I'm doing mine tomorrow night.(diff removed for a regear. I'm cheating a bit)