AT-205 re-seal works like a charm for rear main seal leaks

AT-205 did nothing but drain my wallet.
I'm also using 10W30 High Mileage conventional oil, which made little-to-no difference.

I tried all that stuff for a decent leak. The leak didn't go away until I threw in a Mopar seal and used an anaerobic sealant per the FSM.

That said, I'd consider trying AT-205 again for a small/slow leak...knowing that it won't fix an anaerobic sealant failure and the results may not last.
 
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I tried all that stuff for a decent leak. The leak didn't go away until I threw in a Mopar seal and used an anaerobic sealant per the FSM.

That said, I'd consider trying AT-205 again for a small/slow leak...knowing that it won't fix an anaerobic sealant failure and the results may not last.

That’s why I went with the cat litter-fix.
On the bright side, it always has fresh oil in it.
 
That’s why I went with the cat litter-fix.
On the bright side, it always has fresh oil in it.

MY RMS and FMS were leaking oil all over my pan and transmission so I needed to address them.

I did the job all at once including the harmonic balancer, timing chain/guide/sprockets, and oil pump/pickup tube.

Not a fun time, but I'm glad I did all of it bc the parts needed to be updated. The harmonic balancer's rubber was cracking, the chain guide was in two pieces, chain was worn, and the pickup tube to the original pump was extremely sloppy instead of being a tight press fit...yikes.

I went into that job feeling like I was going overboard buying all of those parts for a 200k engine. I've come away feeling like it was a no-brainer since the engine has good compression and runs well even with 7 psi of boost applied.
 
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AT-205 did nothing but drain my wallet.
I'm also using 10W30 High Mileage conventional oil, which made little-to-no difference.

As for how to 'recover' a fresh oil change with a dripping drain plug, catch it all in a CLEAN container then pour it back in after replacing the drain plug & washer.
Must not have cleaned the underside of the crush washer and had this annoying leak from the drain plug. I was ready to drain it and start over, but I just backed the plug out enough turns to get a shop rag under the washer. Cleaned it and the oil pan and topped her up. Problem solved.

Still no sign RMS leak.
 
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Must not have cleaned the underside of the crush washer and had this annoying leak from the drain plug. I was ready to drain it and start over, but I just backed the plug out enough turns to get a shop rag under the washer. Cleaned it and the oil pan and topped her up. Problem solved.

Still no sign RMS leak.

Thanks for this thread and reporting your results intermittently. I had a pretty bad leak in a ‘14 GMC 5.3L. I replaced the oil cooler block off plate gasket and added the 8oz of AT-205/6qts oil about 1400 miles into fresh oil. I drove for 15 minutes and checked. Still leaking. Drove another hour and five minutes. Not much more oil leak. Cleaned it all up. Went for a drive the next day. Nothing. Bone dry!
 
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Thanks for this thread and reporting your results intermittently. I had a pretty bad leak in a ‘14 GMC 5.3L. I replaced the oil cooler block off plate gasket and added the 8oz of AT-205/6qts oil about 1400 miles into fresh oil. I drove for 15 minutes and checked. Still leaking. Drive another hour and five minutes. Not much more oil leak. Cleaned it all up. Went for a drive the next day. Nothing. Bone dry!
Nice. Appreciate that shared this.
 
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