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Unread 10-16-2012, 09:27 PM   #1
x1n54n3x
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1998 XJ Cherokee 
 
Join Date: Mar 2011
Location: Mammoth Lakes, CA
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Major oil leak...Rear Main Seal on 5.2 +more

I've got a massive leak going on and the other night it hit the point where my ZJ was pissing a trail of oil. I've had a small leak for quite some time (the entire time?) and I'm pretty sure the massive fluctuation in temperature this past week finally f-ed the seal to death. (75+ this week, below freezing last week) Anyways, I like to think I'm a capable person with a solid tool set (and a not-so-full bank account) so I'm undertaking this on my own with the help of a couple buddies and a bunch of beers.

I'll be starting with the valve cover gaskets, as mine have always had oil residue on them, I might as well, right? Easy. Don't need much help past the Haynes manual, I've done this on an Audi and it definitely can't be worse than that was.

Then I'll be diving into the rear main. While I'm down there I'll also replace the oil pump and oil pan gasket because it would be terribly inefficient not to.

I'm posting because here because as I've done a fair amount of research, I want to ask everyone for tips before I start tearing apart the undercarriage of my only vehicle.

I will be using the Haynes Manual, as well as various threads I've come across including AprilzWarrior's write up on Mallcrawlin (I cannot see his pictures, that sucks).

That thread can be found here: http://mallcrawlin.com/forum/showthr...mp-Replacement

I've also read that the oil pump needs to be primed. Can someone clarify what this means beyond just pouring new oil into the pickup tube?

Additionally, I'm sitting at stock height which complicates things slightly.

According to upside, among others I've come across, "If your ZJ is at stock height you'll have to disconnect most of the front axle suspension, basically everything except the control arms and driveshaft. You can probably leave the steering hooked up too. Otherwise you can't get the pan past the front axle pumpkin."

Does anyone know of a write up for the front axle suspension removal? I'm sure I can figure it out with the manual I have and rummaging around the internets, but first hand accounts and high resolution as well as color photos go a long way.

The teardown has to happen this weekend, it will be getting significantly colder and possibly turning into full blown winter within the next couple weeks. Definitely not doing this in the rain, or even worse, the snow while it's sub freezing out. I don't have a garage.

So all in all, I'm just looking for some last minute tips and/or resources. Anything and everything is appreciated! Thanks!

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Unread 10-16-2012, 10:36 PM   #2
Uniblurb
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Quote:
Originally Posted by x1n54n3x View Post
I've got a massive leak going on and the other night it hit the point where my ZJ was pissing a trail of oil. I've had a small leak for quite some time (the entire time?) and I'm pretty sure the massive fluctuation in temperature this past week finally f-ed the seal to death. (75+ this week, below freezing last week) Anyways, I like to think I'm a capable person with a solid tool set (and a not-so-full bank account) so I'm undertaking this on my own with the help of a couple buddies and a bunch of beers.

I'll be starting with the valve cover gaskets, as mine have always had oil residue on them, I might as well, right? Easy. Don't need much help past the Haynes manual, I've done this on an Audi and it definitely can't be worse than that was.

Then I'll be diving into the rear main. While I'm down there I'll also replace the oil pump and oil pan gasket because it would be terribly inefficient not to.

I'm posting because here because as I've done a fair amount of research, I want to ask everyone for tips before I start tearing apart the undercarriage of my only vehicle.

I will be using the Haynes Manual, as well as various threads I've come across including AprilzWarrior's write up on Mallcrawlin (I cannot see his pictures, that sucks).

That thread can be found here: http://mallcrawlin.com/forum/showthr...mp-Replacement

I've also read that the oil pump needs to be primed. Can someone clarify what this means beyond just pouring new oil into the pickup tube?

Additionally, I'm sitting at stock height which complicates things slightly.

According to upside, among others I've come across, "If your ZJ is at stock height you'll have to disconnect most of the front axle suspension, basically everything except the control arms and driveshaft. You can probably leave the steering hooked up too. Otherwise you can't get the pan past the front axle pumpkin."

Does anyone know of a write up for the front axle suspension removal? I'm sure I can figure it out with the manual I have and rummaging around the internets, but first hand accounts and high resolution as well as color photos go a long way.

The teardown has to happen this weekend, it will be getting significantly colder and possibly turning into full blown winter within the next couple weeks. Definitely not doing this in the rain, or even worse, the snow while it's sub freezing out. I don't have a garage.

So all in all, I'm just looking for some last minute tips and/or resources. Anything and everything is appreciated! Thanks!
I'd definitely use a Mopar pan gasket and rear main seal, probably the valve cover gaskets too. While a bit more pricey it's worth it to not have leaks if done right.

Below are a couple links/threads from when I did my 96 4.0 rear main seal and pan gasket. There's some good videos/links in the threads and while most are for a 4.0 much still applies to the 5.2.

The summary for the below one is you need to remove the top shock nuts, the sway bar link nuts (I did bottom w/lg. torx bolt since I thought top one would snap) and the track bar bolt to drop your axle. But also some good tips for sliding in the top rear seal w/vids so you don't tear it up.

http://www.jeepforum.com/forum/f13/o...83/index2.html

Best to read the below one before you remove your track bar bolt. Had some great help/tips from others on this forum for putting the wheels/tires on the ground, turning the steering wheel, and letting the body create slack in the track bar bolt or aligning the hole up.

http://www.jeepforum.com/forum/f13/t...-bolt-1367135/

I didn't put silicone gasket sealer on the corners or any other part of the pan gasket as in the write-up you posted. But I did put anaerobic gasket sealer on the corners where the rear main seal meets the block and on the cracks where the front/main block parts comes together. No leaks so far.

I'm not sure if a 5.2 has an oil filter adapter or not? But a 4.0 does and for $5-$7 from the dealer you can get a 3 o-ring kit to fix it from leaking. Mine was leaking pretty good but couldn't tell where it was coming from because it would blow back and come out of the bottom of the front of the bell housing. Just thought I mention this but may not apply to your 5.2.

I'd start hosing down your axle dropping bolts/nuts now with PB or some other good rust cutter. The sooner you put it on the better. Good luck!
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-Stalling ZJ? 12 things to check before replacing a sensor; the Dirty Dozen
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Unread 10-17-2012, 06:31 AM   #3
Snowfan2
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96 5.2 4x4...I did my rear main and oil pump a few weeks ago. I disconnected shocks at bottom, removed steering stabilizer and did not mess with the sway bar. Start there.
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Unread 10-18-2012, 06:45 PM   #4
x1n54n3x
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Thanks uniblurb and snowfan, I ordered the gaskets the other day, should be here today. I'll pick up some rust cutter and some degreaser when I pick all of that up.

Supposed to snow 1-3 feet next week, I'm in a race with nature.
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Unread 10-18-2012, 07:22 PM   #5
Kevinyj95
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Becarful putting in the new rear main Sometimes you can slice it on the lip. When I was at stock height I had to drop it all besides the CAs and driveshaft. The pick up tube gets in the way of turning the pan out. I would use a little rtv not alot just on the outside of the rear main but like I said you push it in too fast and it will slice. So you may want two just incase. Its easier than it looks. Two jack stands and a jack. Remember the axle has to come down alot. Dont over tighten the oil pan bolts.
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Unread 10-18-2012, 07:25 PM   #6
Kevinyj95
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Snow god no. I still need to do an engine swap in a wrangler damn winter.
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Unread 10-18-2012, 07:38 PM   #7
dusterdude
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Geez ub,have you never heard of fel-pro and op pack the pump gears with vaseline
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Unread 10-19-2012, 12:09 AM   #8
Uniblurb
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Quote:
Originally Posted by Kevinyj95 View Post
Becarful putting in the new rear main Sometimes you can slice it on the lip. When I was at stock height I had to drop it all besides the CAs and driveshaft. The pick up tube gets in the way of turning the pan out. I would use a little rtv not alot just on the outside of the rear main but like I said you push it in too fast and it will slice. So you may want two just incase. Its easier than it looks. Two jack stands and a jack. Remember the axle has to come down alot. Dont over tighten the oil pan bolts.
Know what you mean and I sliced the back off of the new top rear seal even going in slow. It helps to shoot some liquid soap up in the slot w/a plastic syringe and couldn't have gotten it in the slot correctly without a plastic tab. From one of the earlier links.

http://www.jeepforum.com/forum/f13/o...l#post13519548


Quote:
Originally Posted by dusterdude View Post
Geez ub,have you never heard of fel-pro and op pack the pump gears with vaseline
To each his own dd and I'd just prefer OE Mopar gaskets and sensors.
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-Stalling ZJ? 12 things to check before replacing a sensor; the Dirty Dozen
-Crankshaft position sensor multimeter test. & video of testing.
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Unread 10-19-2012, 12:34 PM   #9
Snowfan2
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Your seal may leak a bunch for a day or two after fixing, don't worry, it will stop.
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Unread 10-19-2012, 12:41 PM   #10
x1n54n3x
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Your seal may leak a bunch for a day or two after fixing, don't worry, it will stop.
What's this initial leaking from?
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Unread 10-19-2012, 01:29 PM   #11
Uniblurb
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My rear seal and oil pan gasket didn't leak a drop after fixing. Don't know why it would leak after replacing and then stop?
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-Stalling ZJ? 12 things to check before replacing a sensor; the Dirty Dozen
-Crankshaft position sensor multimeter test. & video of testing.
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Unread 10-19-2012, 05:17 PM   #12
Snowfan2
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Originally Posted by x1n54n3x View Post
What's this initial leaking from?
I'm not too sure. After I did my rear main with new pan and gasket it leaked pretty bad. I thought I must have failed. A day or two later, no drops. Went under and wiped up what was left and now 5000 miles later, dry as a bone.

Wanted to mention it in case yours leaked a bit...wait a few days.

It was not from puddled oil behind the inspection plate...brand new clean stuff. A mystery I guess.
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Unread 10-19-2012, 05:53 PM   #13
x1n54n3x
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dude at Napa ordered a FUEL pump instead of an OIL pump. It should still make it to Mammoth by tomorrow morning, just starting a little bit later than I had wanted to. Bought some degreaser, I'll be spraying that filthy b- down once I'm off work tonight, then a nice coating of lube that will sit overnight for the difficult bolts and such.
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Unread 10-20-2012, 09:06 AM   #14
Kevinyj95
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Before you start it to ensure you primed the pump good pull off the coil ignition wire and turn the key to start her let her get up oil pressure. You do the same thing with old cars that have sat for years. If more people did this on fresh starts we would all have better bearings. The alternitive to this is to take off the dist and use a drill. pita just use the starter to turn the engine get her all lubed up.
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Unread 10-20-2012, 05:05 PM   #15
x1n54n3x
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Replaced the valve cover gaskets and then started to get to work on the rear main. It turns out that the transmission is also leaking, though much more heavily than the rear main. I thought it was all oil because oil from the rear main was leaking down onto where the transmission was leaking- the two fluids were mixing causing me to think it was all oil and thus a simple (hah) rear main replacement would make everything fine. Stupid me. Anyhow, I tried to seal up the trans leaks the best I could (I know this is a very ****ty way to deal with a leak) with RTV silicone (I have no means of dropping a trans) and let it dry. Started it up and it poured out from above the starter. Can't see where it's coming from, nor can I even get to it without dropping the trans. I'm over it. Jeep is for sale, 1200 obo. I've replaced a ton of **** on the good ol yeep and a transmission is where I draw the line and say "time for a different money pit".

It's been real jeepers, I've had so much fun with this vehicle and maybe when I have a garage I'll pick up another one as a toy. I need a reliable 4x4 capable of 8000+ft living, period. I have no problem replacing everything on my own- except for transmissions and engine internals. Everything else I can handle. Anyways, this blows, it's going to snow in like 48 hours and I don't have a car now. Time to scramble. PM me if you're close and want to talk about a purchase.
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