Using an additive to fix a rear main seal leak

I also agree with what @Jerry Bransford said early in this thread. Personally am not a fan of these types of additives as they typically add to other challenges later in the vehicle's life.
 
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I'm convinced! I'm going to try the high mileage oil asap

@Jerry Bransford Jerry it seems like most high mileage oils are syn blend, ie Castrol, Valvoline Maxlife, etc. I know you said conventional though. Thoughts on a syn blend if its "high mileage"?
 
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Only time to add a stop leak is right before you plan to sell the vehicle. Some are seal conditioners, and soften the rubber, some are a thick goo that may or may not blend with the oil, and seek out any small hole to fill... passageways included.

High mileage oil is designed to keep the seals conditioned and working smoothly. I will continue to use high mileage in my jeep, we have had the Jeep since delivery in 2005 (new with 8 miles on the clock) and plan to pass it on to our 8 year old. Have been using the high mileage oil since 100k miles, and other than the rear pinion seal finally giving out this summer (130k miles) the Jeep doesn't drip a drop of oil.
In an Ideal world we would all have had a TJ from brand new 8 miles on the clock, So respectfully many owners have no idea how their TJ was serviced and used V abused so I respect your comments :) but I have no idea who was driving my TJ before me so I like others are looking for solutions to problems that may or may not be actual problems!

Now lets face it running 20w 50 will do Zilch damage to a worn 4.0L engine in temperate climates and additive's will work or not but they will do no damage to a worn engine.

To sell a vehicle with additives put in just to get a sale is the reason I do not trust any PO.
I mean come on! some people on here think you should change gear at 4,5 to 5000 RPM because the 4.0L likes it lol
 
So respectfully many owners have no idea how their TJ was serviced and used V abused so I respect your comments :) but I have no idea who was driving my TJ before me so I like others are looking for solutions to problems that may or may not be actual problems!
I bought my one owner Rubi from a retired Air Force guy who was anal with the records he kept from the first oil change until he sold it to me. It makes absolutely no difference in what's going to happen to a used Jeep, regardless of mileage. It's just luck in most cases. :cool: I've had to replace an O2 sensor, TPS and now a decal that faded. That's just too much in the short 4 years I've had (off and on) this damn "Money Pit".
 
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I'm convinced! I'm going to try the high mileage oil asap

@Jerry Bransford Jerry it seems like most high mileage oils are syn blend, ie Castrol, Valvoline Maxlife, etc. I know you said conventional though. Thoughts on a syn blend if its "high mileage"?
Synth blend will not cut it for what you are looking for! 10w is what you need 5w is too thin 5W you would choose winter oil in Alaska or Siberia not NY.

Look at the problem ask the question and make a decision but remember the environment in the prosses, dumping brand new oil is not very smart when you consider oil companies just add "Additive's" so can you. :)
 
I recently purchased my 97 TJ from a guy who always used/change oil with synthetic. When I got it home I notice a daily drip. After reading all this forum I decided to switch to high mileage conventional oil and so far no more leak. I did not add any additives, just oil.
 
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I noticed the leak after I used BG MOA additive along with conventional oil after hearing a mechanic on a local talk radio show raving over the product. I'm afraid that is what caused this as it never leaked before using that additive. I have since switched to just plain oil syn blend. I still see a small leak after that. Part of problem is I don't drive the jeep that much as it is not a daily driver & it's my summer "fun" vehicle.

I see another product called AT-205 with even better reviews. I'm leaning towards trying it even though most of these additives say it has to be driven for a while before it starts working.
I'm convinced! I'm going to try the high mileage oil asap

@Jerry Bransford Jerry it seems like most high mileage oils are syn blend, ie Castrol, Valvoline Maxlife, etc. I know you said conventional though. Thoughts on a syn blend if its "high mileage"?
Not Jerry, but I ended up finding High Mileage conventional oil at Advance Auto Parts under the “Fram” label. Everything else was a blend.
 
To sell a vehicle with additives put in just to get a sale is the reason I do not trust any PO.

Nobody should, unless they are really good friends, and maybe not even then.

I don't know how it started down there but early on over here the main additive at the used car lot was saw dust. It not only plugged up leaks but it also filled in the gaps of worn out bearings so they wouldn't be heard knocking. At least that's what my dad was told by the old guys when he was a youngster 70 years ago.
 
As others have said, it's getting hard to find "high mileage" and "conventional" oil.

Today I checked several mainline automotive stores, and a couple of the big department stores. There is almost nothing in a name brand, but a few store brands still have those attributes. Those store brands are probably okay, but who really knows? Even some of the big name brands do not say "synthetic" anywhere on the bottle, but the manufacturer web page says it's a syn blend. They all have been busy renaming their oils and blending in synthetics.

Are there any recommendations for a specific 10W-30 conventional high-mileage oil?
 
NAPA's engine oil is made by Valvoline and they have a High Mileage conventional 10W-30. https://www.napaonline.com/en/p/NOL75300?impressionRank=2

The information confirming it's a conventional was a little sketchy so I actually called Valvoline who confirmed the 10W-30 version is indeed a 100% conventional. The Valvoline rep confirmed their non-10W-30 versions are blends or synthetics.

 
NAPA's engine oil is made by Valvoline and they have a High Mileage conventional 10W-30. https://www.napaonline.com/en/p/NOL75300?impressionRank=2

The information confirming it's a conventional was a little sketchy so I actually called Valvoline who confirmed the 10W-30 version is indeed a 100% conventional. The Valvoline rep confirmed their non-10W-30 versions are blends or synthetics.

@Jerry Bransford , am I understanding this correctly? Valoline 10w-30 High Mileage (in the red bottles) are 100% conventional? But other weights are not?

If so, great, that’s what I use and never was clear on if it was true conventional or a blend.
 
Valvoline High Mileage in the red bottles is a blend.

blend.webp
 
You need Napa part number: 124403 * - I work with them (Napa) every day. It took a while to narrow this down. If you call and give them this number, they can get it (if they don't already have it)

* Assuming you want Napa Branded, Valvoline 10w30. It's 100% Dinosaur.

--Check that... It's what I found, ordered and used and it was NON-Synthetic. But today the same number pulls up a Synth... Hm...

Try this one: NOL 75305
 
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@Jerry Bransford , am I understanding this correctly? Valoline 10w-30 High Mileage (in the red bottles) are 100% conventional? But other weights are not?

If so, great, that’s what I use and never was clear on if it was true conventional or a blend.
No, only the NAPA 10W-30 High Mileage is 100% conventional. Valvoline no longer brands that combination except for what they make for NAPA.