My Rear Main Seal Adventures

I spent yesterday and today changing my RMS in my 97 with about 130k.

One thing went very well. I dropped the oil pan and when the last bolt came off it dropped onto the linkage -- no prying or anything.

Immediately, however, I realized there was not enough room to slide the pan out. I worked for probably three hours before giving up. On this site, I read someone say that you need to LIFT the axle. I know that seems completely counterintuitive, but not when you really think about it. As the axle drops it also moves BACK toward the rear. But, when you raise the axle, the axle also moves FORWARD. With the heep in jack stands I carefully and slowly placed the jack under the front differential. The oil pan nearly fell on the floor. REMEMBER --- LIFT the axle --- regardless of how counterintuitive it may seem at the time.

Everything else came out and cleaned up fine. There was some scraping, but VERY little and, for that, I am pleased. My engine looked very clean --- very little sludge.

NEXT PROBLEM, the rear main itself was stuck. I started with a copper drift and rubber dead blow mallet. Next, copper drift and regular hammer. Next, a steel drift and a regular hammer. I worked for a long time again. Gave up and slept on it. I searched this site again and found my answer. I took a small strait blade screw driver and place it between the block and the rear main and drove it in very little on both sides. Two blows with the hammer and it was out. Pulled out with the needle nose very easy.

I inserted the RMS and it was difficult. I shaved the top of it off. Back to the store for a new RMS. It went in, not easy, but easy compared to what I have been through.

NEXT PROBLEM, with everything ready to go and the blue gasket in place, using only a small amount of RTV on the corners I put the pan back in place. It was not hard, but impossible to do and not rub the gasket off as I slid it in place. With the oil pan under the linkage I reached over the side of the pan and worked for about ten minutes to get the seal into place. I don't know how this effected the RTV corners, but I knew that I could not pull it out and put it back in without rubbing it off again. My torque wrench only goes down to ten pounds. I put it on a lug nut to see how ten pounds felt and then torqued the oil pan bolts a little less than ten pounds.

SO NOW --- I put in six quarts of Royal Purple 10w30 --- API-SL -- specially made for older engines with flat tappets, a Mobile 1 oil filter, and went for a drive. No leakage, but I am not yet celebrating.

Hope this helps anyone else who has the same experiences as me.

I just changed mine and everything went well. The fun part is having the oil constantly dripping down on you while you are removing/installing the RMS. I don't see how lifting the axle gains any clearance though. You are lifting the entire Jeep when you lift at the differential which gains you nothing. I lifted the body of the Jeep which allowed the front axle to droop which in turn gave me the room I needed to remove the oil pan.

Yeah...RMSs are fun. Im not sure I agree with the axle movement due to lifting it though...

When a stock jeep, the front arms are almost perfectly horizontal. So moving it up would cause it to move back...and moving it down would cause it to go back. It moves in an arc sorta.

Either way...good work on getting it done. On my 01, Im getting the feeling that Im going to have to change the RMS and the oil filter adapter o-rings. Im going to swap front axles when i do my lift, and since I like to plan ahead, Im going to do all that without a front axle. Worlds easier.

I did all that to my 94 a couple years ago. It was lifted then though so it was much easier. But its been leak free ever since and its a great feeling! haha

J.

Maybe I'm crazy --- it seems like most of you don't agree with lifting the the axle. But --- here is what it was like for me. First, I put it on jack stands with the wheels completely off the ground. The axle drooped and moved to rear. The control arms dropped down so that they were not horizontal. When I jacked the differential, the Heep was still on the jack stands. I only raised the diff about 4 inches so the axle was still lower than it would be if it were just sitting on the ground. As I raised the axle, the control arms became more horizontal (but not completely horizontal) and pushed the axle toward the front of the heep -- maybe 1.5 inches. Overall, the axle was still drooping. It was just a matter of finding that "best of both worlds" point where the axle was drooping enough to be lower, but raised enough to move toward the front of the heep.

I read posts where people were removing the axle, lifting the engine, and doing all sorts of stuff to get it out. This stuff was out of my league and I was enormously happy to figure this out.

Another thing I did that I forgot in my first post --- I turned the wheels all the way to the left. This moved the steering linkage to the side so the pan wouldn't hang on it.

In the end -- it was just a puzzle that took me two days to solve.

OOOOOOH... so you originally had the jeep lifted by the body, and the axle was drooping. I gotcha.

Whenever I do that stuff I lift from the axle and use stands under the axles. Its hard to lift my body high enough to do anything anymore...well on the 94.

When I read your post I assumed you ahd it supported by the axle, and you were lifting the axle (compressing the suspension). Thats why you are getting confusing responses

But yes...I agree with you now. WIth the axle in its static position, the pan will slide out easier.

J.

This must have been rear main seal weekend. Sounds like mine was a lot bigger pain than yours. Mine is an old 87 though.

ghettocruiser said:

OOOOOOH... so you originally had the jeep lifted by the body, and the axle was drooping. I gotcha.

Whenever I do that stuff I lift from the axle and use stands under the axles. Its hard to lift my body high enough to do anything anymore...well on the 94.

When I read your post I assumed you ahd it supported by the axle, and you were lifting the axle (compressing the suspension). Thats why you are getting confusing responses

But yes...I agree with you now. WIth the axle in its static position, the pan will slide out easier.

J.

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I agree -- I was not clear about what I did in my first post. I would not lift the entire weight of the jeep by the diff, much less climb under it while it was supported at the diff. The axle was definitely drooping down. I just used the jack under the diff to lift the axle a little so that it was drooping less. I also usually put the jack stands under the axle. But, on this job, I put them under the frame just so the axle would droop.

Jed -- sorry to hear about your troubles. Glad you got it done though. I am still a little scared to celebrate. I keep expecting to walk out to the heep keys in hand only to find 6 quarts of royal purple underneath it. I am not sure when I will stop holding my breath on this one.

ok thanks for all the info! looks like im gonna be waiting for it to warm up a bit before attempting this job. i'll wait to see which way works best i guess. cuz my xj is still stock.

Just a tip. Bread ties do wonders for holding the oil pan gasket to the oil pan when reinstalling.

When I changed my oil pan gasket I used a highlift to raise the front end up. My Jeep looked like one from Jeepspeed heading through the desert. My oil pan was a pain in the butt to get off.

smokeman said:

Just a tip. Bread ties do wonders for holding the oil pan gasket to the oil pan when reinstalling.

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Now THAT is some good advice!!

Is the 'blue (oil pan) gasket' a one piece?

smokeman said:

Just a tip. Bread ties do wonders for holding the oil pan gasket to the oil pan when reinstalling.

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Why didn't you post this Friday :twak: :smsoap:


Yes, the blue gasket is a 1 piece and a heck of a good gasket.

Man, that lift advice was sorely need 3 weeks ago. It has taken me 3 weeks to change my RMS and I'll be finishing tonight. *Sigh*

The first 2 weeks consisted of 4 evening of my cursing at the F-ing oil pan and the axle that was in its way. I disconnected my shocks, my sway bar end links, and something up front (possible tie rod?) and STILL had a bitch of a time getting it out. I had to basically twist the pan sideways to get the right angle to get it out. I also disconnected the steering damper, which made a list of its own problems when the pin stripped.

The seal itself took a night of cursing and one night of deliberating to get it out. I tried a punch with a small sledge and nothing. Tried putting in a screw to catch the rubber and pull it out with a claw hammer. DON'T do that, scratches the crank, trust me. Then I tried to torch it to expose the wire so that I could grab it. RMS does not melt, FYI.

Another round with a punch and sledge get it out. I coated the new one in oil and it went in without issue.

Getting the pan back in - JUST AS BIG A PAIN. More tilting to get the right angle. One tip: Put your gasket onto the pan with RTV and let it sit for a couple hours. This will make it tacky enough that it won't come off while messing with the pan. Unfortunately, I had out RTV on the other side of the gasket to get the best seal. Well, with all the moving it around I got RTV everywhere. *sigh* I was too frustrated to clean, so it's yet to be seen if it'll cause issues.

Tonight I finish bolting up the pan at 6lbs/torque. So annoying, but ideally satisfying to be able to park and not put a piece of plywood under to catch the oil.

Thanks for the tip for the future!

I am currently struggling with maneuvering the oil pan out from behind the axle! Thank God for this site! Unfortunately, I have tried to remove the steering damper bolt. Like every other bolt on my XJ, it is frozen. The end is now mushroomed from being hit with a hammer. That should be fun to try to fix! I'm gonna go play with the axle now! Thanks for the thread!

Did you guys remove the oil pump prior to getting the oil pan out? Or were you able to get the pan out without removing the pump? I can't seem to access the rear bolt on the oil pump. Any tricks?

Its an XJ, everything about it is counter-intuitive...lol Glad it worked out for you.

Stockton said:

Did you guys remove the oil pump prior to getting the oil pan out? Or were you able to get the pan out without removing the pump? I can't seem to access the rear bolt on the oil pump. Any tricks?

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I didnt touch my pump. I pulled the oil pan with the front diff at full hang.:looney:

It took a lil persuasion not much but it slid out.

In looking toward the rear of the oil pan, it seems to be getting caught on either the exhaust pipes or whatever that cylinder shaped thing is that goes into the bell housing of the transmission--eg. sandwiched between them. Haynes doesn't say anything about this, other than to remove the bell housing. Did you remove the entire bell housing? Or just the flat cover between the housing and the oil pan? Thanks for the help.