Best Additive For Small Rear Main Seal Leak???

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I have a 1999 Mitsubishi Eclipse. It has 133,000 miles on it. It's a 5 speed. I've never had any major problems with it, knock on wood. I had to take it to the garage to have them find an oil leak. They said it was the oil pressure sending unit and replaced it. They also noted that the rear main seal was leaking about a drop or two of oil ever 45 minutes. I know that's not much oil at all. I do not want to replace the rear main seal due to the high cost of it(Estimated $600 or $700). My question is what should I do? I am a compulsive and addicted researcher and reviewer. I research and review almost EVERYTHING I buy. I have read multiple posts and reviews, both positive and negative about Bar's Leaks Rear Main Seal Repair, Lucas Engine Oil Stop Leak, Auto-RX, Marvel's Mystery Oil, etc. I am kind of at a standstill and can't decide on what to try to fix the leak. I have never used any stop leak product or additive in my life! Any input, review, or personal usage report would be greatly appreciated! Thank you all for your time!
 
I would try using a high mileage oil , if that does not seem to stop the leak I would try the Bar's leak rear main seal repair. What oil are you currently using?
 
I used Val. Maxlife 5-30 and it stopped the same type of oil leak in the Camry... Try that 1st.
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I am currently using Castol GTX High Mileage. On that note, I have tried a LOT of different oils. I have never tried a fully synthetic though. Also, I never knew the rear main seal was leaking before recently. In the past, the car has been using oil. I can honestly say I don't know how much because I hadn't been using it was my daily driver until recently. I wanted to start checking it and recording all results but that has gotten messed up since it started leaking oil via the oil pressure sending unit. I want to get a detailed diagnosis about how much oil it's using now that the main leak was fixed. I'm just trying to determine how to go about fixing the rear main seal leak first. I have read very good things about Valvoline MaxLife on here as well as Mobil Clean 5000. As far as the Bar's Rear Main Seal fix is concerned, should I worry about it "gunking" up my engine? I am very open to trying about anything based on the good reviews I've read on here about MMO, Auto-Rx, etc. I know they are cleansers in a sense and worry about them making the leak worse. I'm kind of all over the place as far as a "fix" on this one. I start reading and I get my mind running on all sorts of products! I'm definitely OCD when it comes to wanting what's best for my vehicles!
 
Thanks for your input! I have read good things about Maxlife oil! I'm almost due for an oil change so I may just try that first before going with the stop leak product.
 
+1 on the Valvoline Maxlife , its a great oil and is pretty thick in the 5w-30 or 10w-30 flavors so I would give that a shot. I use it in my girls saturn ion and have had zero problems.
 
Do you think that would cut down on oil consumption as well as fix the leak? As I stated before, I definitely want to figure out exactly how much it's leaking per month or 1000 miles.
 
Try the Maxlife. It has gotten a lot of great reviews. If it does not aid in oil consumption/leakage, then move to the other additives or a thicker grade of oil such as 10W40 high mileage. Stay away from the MMO and Auto RX as neither will help you with a leaking rear main seal. If you wanted to clean up an engine or free up a sticking lifter then maybe you could try them. Stay safe and just try the max life. If you are still getting some leakage, maybe try the max life 10w40.
 
Well I can give you my experience with rear main seal leaks. On a 92 GMC pick up, I was using PP 5 and 10/30 and it would pour out. Tried Auto rx, nothing. Went to Castrol 15w/40 and the leak almost completely stopped. Currently have a chevy 1500 that was leaking when I bought it, used Auto RX, and the leak almost vanished.
 
Thank you all for your input. I am going to start with trying Maxlife and see what happens. Have any of you used Bar's Rear Main Sealer?
 
Originally Posted By: wemis
Thank you all for your input. I am going to start with trying Maxlife and see what happens. Have any of you used Bar's Rear Main Sealer?

I have used the leak sealer on a honda accord that had about 280k , it worked a little bit but did not stop the leak. However this was a big leak and I dont think anything short of replacing the seal would have fixed it . In the end we just donated the car to charity and got a used car. I would just try the Maxlife in 10w-30 , its a pretty thick 30 weight with a good seal conditioning additive package so that would be my first shot then after that 10w-40 and failing that the Bar's Stop leak.
 
if the car is a stanard you had better get it fixed quick or you will be buying a new clutch soon.
i would go maxlife 10/40 or 10/30 with lucas
 
I used a lot of stop leak products to stop two leaks I had to avoid having to pay to have it done. They were an annoyance to say the least. Only one product worked - No Leak: http://www.goldeagle.com/brands/no_leak/default.aspx

Within 200 miles, my engine seal leaks stopped. I then used their stop leak for a power steering leak on my steering rack. That leak stopped within 200 miles where nothing else ever worked. I was able to avoid having to spend $1,100 plus dollars on a new rack with labor and re-alignment as well as the cost of the engine seals and the labor associated with that. I am a happy camper. That was some time ago. My driveway is finally clean.

Not saying it will work for you, but it sure worked for me; and, No Leak is the cheapest of all of them. Go figure...

I should add that these leaks were not gushers. They were leaks.
 
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For a real small leak i might try Max life or ARX.
Not my favorite product for other issues but to be fair a lot of folks seem to have some success with it in these cases,i think its probably a lot safer than a lot of stop leaks that will swell seals up like an elephants trunk,something you really don't want.

A major leak at the rear seal indicates seal damage and will need to be replaced,don't toast the rest of the seals with a product that swells them up trying to fix this one.
IMHO use the least aggressive product.
 
Thanks for the review of the No Leak product. I had never heard of it. I am going to try MaxLife 10W-30 first to see if that fixes it. If it doesn't, I am going to try the stop leak products. Since it's not a gushing leak and is very small IMO, there has to be at least ONE stop leak product that will fix it! Thank you all for your knowledge and input! I greatly appreciate it!
 
Maxlife semi syn 10W30 is your best bet. A few drops is not that bad and after about one OCI(3K)miles with Maxlife your seal should seal up. I have done this with some of my classic cars and was really surprised how well it worked.
 
There is a product called ATP AT-205 ReSeal liquid.

I would contact ATP's tech dept. first for dosing suggestions, as this stuff is almost PURE esters, and (as Trav has stated) too much will turn EVERY seal into MUSH!
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The LubeGard Bio Tech Engine Protectant (in the blue bottle) contains some mild esters which might help as well (but it may not be strong enough for your needs).
 
I know a very reknown oldschool mechanic who swears by the Bars Rear Main Seal Leak. He rebuilds many engines and is a big Jeep guy and says he uses it in every motor he rebuilds!
 
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