Does this look like a rear main seal leak?

jblues1969

jblues1969

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Does this look like a RMS leak? Not a lot of leakage, maybe 2-3 drops a week.

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Before you do anything, verify that your valve cover bolts are snug. Also verify that your oil pan nuts/bolts are snug. I thought I had a RMS leak only to find out that I had a lot of loose nuts and bolts. After tightening everything up, clean the surfaces real good and then wait to see if it still leaks.
 
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Yep that's most likely either a RMS leak or a valve cover leak. If you isolate it to the RMS leaking, try this before paying someone to replace the RMS which is a PITA job. If you're running a synthetic engine oil, know that they're well known for leaching all the natural oils/lubricants in the RMS which dries them out and makes them leak. Switch your engine oil to a 10W-30 High Mileage CONVENTIONAL like Pennzoil and drive it for a week or two. Even if you're running a conventional still switch it to a High Mileage. High Mileage engine oils have additional restorative products that can restore a RMS back to good condition. Odds are very good it'll fix/cure the RMS problem. I had a major RMS leak in my daily-driver BMW and doing this cured the leak in 4-5 days of daily driving. It's a good thing too because I received two quotes for close to $2,000 to replace my BMW's RMS.
 
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I had Goodyear do my first oil change with this jeep because I was afraid I'd do something like break off the oil filter and not be able to drive the jeep to get it fixed. I believe they used high-mileage synthetic blend oil. Next change, I'll go with conventional high-mileage.

Jerry- do you think an additive like Bars Leaks or Lucas Oil Stop Leaks is a good idea?
 
Jerry Bransford said:
Yep that's most likely either a RMS leak or a valve cover leak. If you isolate it to the RMS leaking, try this before paying someone to replace the RMS which is a PITA job. If you're running a synthetic engine oil, know that they're well known for leaching all the natural oils/lubricants in the RMS which dries them out and makes them leak. Switch your engine oil to a 10W-30 High Mileage CONVENTIONAL like Pennzoil and drive it for a week or two. Even if you're running a conventional still switch it to a High Mileage. High Mileage engine oils have additional restorative products that can restore a RMS back to good condition. Odds are very good it'll fix/cure the RMS problem. I had a major RMS leak in my daily-driver BMW and doing this cured the leak in 4-5 days of daily driving. It's a good thing too because I received two quotes for close to $2,000 to replace my BMW's RMS.
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Jerry, I use 10-30 Diesel oil in my 6cyl 1959 Chevy 235 engine because of the zinc etc it contains. Have you tired it before?
 
RVAH-13 said:
Jerry, I use 10-30 Diesel oil in my 6cyl 1959 Chevy 235 engine because of the zinc etc it contains. Have you tired it before?
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No, our stock Wrangler engines require no additional zinc as our cam lobe pressures aren't high enough to require it with stock cams and stock valve springs. Now if I was still running a hot-rod engine with a high-lift cam, stiffer valve springs, etc. damned straight I'd add more zinc. But for our Wrangler engines it's simply not needed. That's why Wrangler owners aren't constantly bitching about our engines having wear issues related to a lack of zinc... because it's not a problem which means they're getting enough zinc to prevent them, despite the claims of some zinc zealots.
 
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I switched back to high-mileage conventional oil + Bar's Ream Main Seal Repair additive. My leak stopped dripping. I realized it's not fixed, but no more drips on the skid plates and ground.
 
explorerlyon said:
I switched back to high-mileage conventional oil + Bar's Ream Main Seal Repair additive. My leak stopped dripping. I realized it's not fixed, but no more drips on the skid plates and ground.
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It's fixed. Neither of those simply plug the leak, both work on the RMS to restore it back to its original size and consistency.
 
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Still waiting for the AT-205 to resolve our leak.
I haven't driven it the 4-5 hours they claim is typically required to resolve most leaks since adding it.
 
TheBoogieman said:
Isn't that the definition of fixed? o_O:unsure:
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Well now you got me curious- I’m gonna have to dig into this- I think I’m going to start a committee....

My dog is fixed-

My price on plywood is fixed-

The game was fixed-

I’m fixing to go to the store-

I bet English is hard to learn. I might give it a shot.
 
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Jerry Bransford said:
Yep that's most likely either a RMS leak or a valve cover leak. If you isolate it to the RMS leaking, try this before paying someone to replace the RMS which is a PITA job. If you're running a synthetic engine oil, know that they're well known for leaching all the natural oils/lubricants in the RMS which dries them out and makes them leak. Switch your engine oil to a 10W-30 High Mileage CONVENTIONAL like Pennzoil and drive it for a week or two. Even if you're running a conventional still switch it to a High Mileage. High Mileage engine oils have additional restorative products that can restore a RMS back to good condition. Odds are very good it'll fix/cure the RMS problem. I had a major RMS leak in my daily-driver BMW and doing this cured the leak in 4-5 days of daily driving. It's a good thing too because I received two quotes for close to $2,000 to replace my BMW's RMS.
Click to expand...

I replaced rear main seal and oil pan gasket a couple days ago. Rear main now seems to be leaking quite badly. It drips a lot very quickly right after driving and especially when I am parked so that the back of the car is downhill. I know for a fact that my valve cover is leaking as well, parts are orderd for that, but I dont think it is this bad, and I think that this picture points directly towards rear main seal leakage
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this is the oil I ended up using just because it is what was available in a close-by store. What do you recommend I do? Should I take it all apart again and just make extra sure to install rear main perfectly, then replace with your recommended oil, or should I just try a different oil now? The leak seems to be pretty substantial which is why I am leaning towards doing the whole thing again... Thanks
 
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My bet is the RMS installation didn't go as planned, changing to a High Mileage oil is not likely to help at all. I'd install a new RMS after viewing a couple YouTube videos how it's done with the 4.0.
 
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