Rear Main Seal concern???

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Getting ready to purchase my neighbors 2000 Dodge Ram 4WD 5.2L with the automatic transmission/overdrive tomorrow when he has off work in the morning. He is the original owner and its parked with exactly 93,014 original miles. Climbed underneath it today and noticed the rear main seal has small drops on it. He says he ran exclusively PYB 10W30 with a Mopar filter his whole ownership. What kinda job is it to replace a RMS or would throwing high mileage oils at it be my best bet for now? Does Liquid Moly not also make a product specifically for RMS leaks?

Note -- he bought a brand new 2018 Jeep Cherokee and his wife no longer wants the truck sitting in the driveway. I offered him $2500.00 and he said, "done deal!!!"

Dale
 
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You could try using some HM oil and it may stop.
Replacing the seal involves a lot of work, at the minimum transmission has to come out along with the transfer case.
 
You could try some HM in it and see if it makes a difference.
IMO, it makes more sense to monitor it, and if it is "only a few drops,"
top off if necessary.
That's what I do on my '03.
Doesn't make sense on an 18 year old truck to replace it unless the leakage becomes severe, or other repairs make the replacement feasible.
 
Do 2-3 OCIs with a HM oil and see if that stops the leak. The cost difference is negligible if you buy on a sale/clearance.
 
Rear main seals are cheap, usually only a few bucks. The problem is the labor involved as the transmission must come out to change the seal. I had a bad rear main leak on the Explorer I purchased in October. I researched a lot on stop leaks and tried blue devil rear main sealer along with 10w30 Maxlife. Within 3K the leak has been greatly reduced. I used to have a large puddle under the engine. Now it's just a tiny spot, if any.

For a few small drops I'd agree, start with Maxlife and go from there.
 
Don't plan on fixing a RMS leak with chemicals. Decide if you can live with it or maybe you have the resources to fix it yourself.

I just got in the habit of keeping a drip tray under the truck when it was parked and checked the oil level often. Surprisingly even with the leak being about a half teaspoon a day the oil level never dropped noticeably in 5k OCIs.
 
I'd leave it and use red bottle Maxlife. May want to replace the pcv valve with an oem unit as well.

I had a 99 Accord 4cyl that had a oozing rms. First Honda dealer quoted $700, second dealer quoted $500. Contacted Honda and they agreed to pay half. So cost $250 but afterwards noticed a flare from 1st to 2nd gear. They did a drain and fill on the trans which took care of that. In hindsight I would have left it alone.
 
Since he has always used PYB, I'd try some PHM 10W30 for a couple of OCIs. BTW, I think you got a great deal on that truck, especially since it's a one-owner vehicle!
 
I wouldn't put anything in the oil or run a HM oil, just keep an eye on it. If all else fails park it nose down and when you cant throw this under it. Sounds funny but not kidding.

 
Me, I'd get under there with a strong flash light and look all over the back of the block. Could be rear "china wall", or oil pressure sender or anything leaking from above. It may be the rear main, but maybe not ...

Throw in a full can of BG 109 and a new PCV and see what happens. If the PCV has been sticking at all, it has been building crankcase pressure and pushing the oil out. If the pressure is reduced, the leak will go away. The BG109 will help loosen any stuck/sticky ring action, so blow-by will be reduced, so less crankcase pressure, less leakage
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Check PCV valve and after that run QSUD with LM Motor Oil Saver. If that stops leak then run HM Pennzoil. If leak returns go LM Motor Oil Saver again.
 
Dude, you got an amazing deal on that truck. In my county in Maryland it would be twice that. My advice? Buy it quick before the guy reconsiders! worry about the oil leak after you own it
 
Will be looking at it more in depth tomorrow when its in my driveway. I received the "free" Shell Rotella 5W30 Multi Vehicle I was gonna use in it but now -- HM oil possibly???


Dale
 
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