Rear main seal

FirstJeep

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Oct 29, 2018
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I have been told that I have a rear main seal leak and am not mechanically inclined at all. I have been told that if I just keep checking the oil and adding oil when needed I will be fine for right now. As I said I am not mechanically inclined and am wondering what a general price to have that fixed would be. By the way, it is a 2000 6 cyl automatic if that helps. Thanks in advance
 
I have been told that I have a rear main seal leak and am not mechanically inclined at all. I have been told that if I just keep checking the oil and adding oil when needed I will be fine for right now. As I said I am not mechanically inclined and am wondering what a general price to have that fixed would be. By the way, it is a 2000 6 cyl automatic if that helps. Thanks in advance
To have shop do it would be fairly pricey. If it isn't dripping onto the ground after parking it for awhile, I wouldn't have it done. Also, no guarantee it will remain leak free after being replaced. Most TJs have wet rear main seals. Maybe try a high mileage oil or change to conventional oil if you're running full synthetic. It can help or even stop the leak if its not a heavy leak. If its still leaking (onto the ground) after all that, then I'd look into having it replaced.
 
Many many leaks have been diagnosed as rear main seal leaks that turned out to be valve cover gasket leaks. I'd degrease and wash the piss out of the back side of the motor then check to make sure where your leak is coming from. Valve cover gaskets are relatively cheap/easy to repair. RMS not so much.
 
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I have been told that I have a rear main seal leak and am not mechanically inclined at all. I have been told that if I just keep checking the oil and adding oil when needed I will be fine for right now. As I said I am not mechanically inclined and am wondering what a general price to have that fixed would be. By the way, it is a 2000 6 cyl automatic if that helps. Thanks in advance
What oil are you running.
 
As above, the use of many synthetic oils will eventually start causing leaks. It's common for that to happen after the engine gets some miles accumulated on it.

Seals tend to dry out with many synthetic engine oils. That said, it's highly (99.99%) likely you can cure it by doing nothing more than changing your oil to a High Mileage CONVENTIONAL 10W-30. High Mileage formulations have extra seal conditioners so they can usually restore the various seals like the rear main seal and valve cover gasket. Good brands like Valvoline, Castrol, NAPA (made by Valvoline), Mobil (not Mobil-1), etc. will be fine.

My BMW lived on nothing but synthetic (only because it said so on the oil cap lol) and it eventually developed a horrible RMS leak. Switching to a High Mileage Mobil conventional 10W-30 cured my leak entirely within 3-4 days.

Since the seal restoring additives in High Mileage engine oils usually restore the seal, I sure wouldn't replace it as a first step. No the High Mileage doesn't just plug the hole, it actually works to restore the seal.

Just make sure it is a conventional and that it says High Mileage.
 
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Like Jerry said above, switch to that exact oil...BTW I was quoted $400 to get my RMS done here in NY. I will eventually do it myself but in the mean time I have switched to the above recommended oil.
 
With the high mileage additives working to actually restore the seals odds are that you won't have to... so long as you stay with a conventional high mileage oil. I don't consider this to be a band-aid fix.
Yeah, I know. I bought all the parts before I tried the oil, I might just do it at some point when bored and want to wrench a bit.
 
I had a rear main seal leak. It would leave a small puddle of oil on my driveway overnight (half dollar size). Puddle looked big, but was small volume. I drove it that way for 6000 miles. I doubt I added a full quart of oil in that time. I could go a few thousand miles before the oil level was low on the dipstick.

I replaced my own seal. It was easy, after I got the exhaust header off. Getting the header off was a royal PITA because the bolt and nuts holding it together were corroded and I had a difficult time getting a bite with a wrench.

If I didn't want to mess up my driveway, I may have held off. Oil is cheap.
 
I had a rear main seal leak. It would leave a small puddle of oil on my driveway overnight (half dollar size). Puddle looked big, but was small volume. I drove it that way for 6000 miles. I doubt I added a full quart of oil in that time. I could go a few thousand miles before the oil level was low on the dipstick.

I replaced my own seal. It was easy, after I got the exhaust header off. Getting the header off was a royal PITA because the bolt and nuts holding it together were corroded and I had a difficult time getting a bite with a wrench.

If I didn't want to mess up my driveway, I may have held off. Oil is cheap.
Do you have to drop the exhaust manifold? just drop the cats to drop the oil pan?
 
Getting the exhaust off sucks. Just did mine a couple of weeks ago and o bet the exhaust was 50% off the time.

To make matters worse, I still have a leak; however, I think it is from the transmission because the fluid is very dirty.

I would definitely try the high mileage oil first.
 
I will definitely try the different kind of oil. What are y’all’s suggestions for the brand of oil. Is there any one oil that’s better than the othe? My Jeep has 155,000 miles on it also if that matters.
 
I will definitely try the different kind of oil. What are y’all’s suggestions for the brand of oil. Is there any one oil that’s better than the othe? My Jeep has 155,000 miles on it also if that matters.
With that many miles definitely go with a conventional (!) High-Mileage 10W-30 engine oil. Valvoline, NAPA (made for them by Valvoline), Castrol, Mobil (not Mobil-1), Pennzoil, Quaker State, etc. all have High Mileage versions IIRC. Just make sure it says High Mileage on the front label so you get the additional seal conditioning additives.
 
Do you have to drop the exhaust manifold? just drop the cats to drop the oil pan?
I dropped the cats with the exhaust header, the manifold remained. In theory, dropping the header isn't too bad, you just need long extensions and patience. I couldn't get a socket or wrench on several of the bolt head or nuts, and the ones I could were rusted and the wrench wanted to strip the head. I think I was one for four. I ended up removing a fender to get better access. I used new hardware when I reinstalled the header.