Just had my car into the garage and I have a leak in the rear main seal. It is a small leak at the moment. I do want to invest much money into the car. it has been totaled once and I only plan on keeping it until I finish college in two years. Would running high mileage oil, or thicker oil (10w-30, 15w-40, or sae 30) help plug the leak temporarily.... On a side note, I had used Mobil Clean 5000 since I got the car in 2006. Last oil change I used super tech and noticed the car comsuming/leaking oil. Could this have played into my situation?
Rear Main Seal
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You dint say what vehicle but, I would use Mobil or Pennzoil HM 10w30, not synthetic. They say will help condition hardend seals so it may take a while to show good improvement.
High mileage oil fixed the rear main seal leak in my Crown Vic. It was a fairly small leak. After making the switch, it consumed something like half a quart in a 5,000 mile OCI. Previously, it consumed much more.
It is definitely worth a try. High mileage oil is not much more expensive than regular. I used Castrol GTX High Mileage, but Valvoline MaxLife seems to have a bigger following and better reputation.
SuperTech is made by Exxon Mobil in some places, and someone else (Warren Performance Products I think) in others. I'm guessing the Exxon version of SuperTech is fairly close to the former Mobil Clean 5000 product.
Different additive packs from switching oil could have cleaned something that was sealing the leak.
It is definitely worth a try. High mileage oil is not much more expensive than regular. I used Castrol GTX High Mileage, but Valvoline MaxLife seems to have a bigger following and better reputation.
SuperTech is made by Exxon Mobil in some places, and someone else (Warren Performance Products I think) in others. I'm guessing the Exxon version of SuperTech is fairly close to the former Mobil Clean 5000 product.
Different additive packs from switching oil could have cleaned something that was sealing the leak.
Rear main seals are one area where a good quality HM oil can help. But even if you do NOTHING, its not going to suddenly turn into a gusher, it'll just "mark its territory" with a few drops every time you park it. Jeep 4.0s are notorious for running hundreds of thousands of miles with slow rear main weeps. I'd recommend Valvoline MaxLife as a good starting point- its a robust oil, affordable, and I know a lot of people who've had good results with it.
It's a 1997 Mercury Sable 3.0 12 valve
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
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Originally Posted By: outoforder
It's a 1997 Mercury Sable 3.0 12 valve
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
Yes, stay in the recommended grade (I assume 5w30) but use a HM oil. Thickness matters a HECK of a lot less with leaks than people think. As in "almost not at all." And the cold vis. number matters even less, since the rear main only leaks when the engine is actually running, and most of the time its running the oil is hot.
It's a 1997 Mercury Sable 3.0 12 valve
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
Yes, stay in the recommended grade (I assume 5w30) but use a HM oil. Thickness matters a HECK of a lot less with leaks than people think. As in "almost not at all." And the cold vis. number matters even less, since the rear main only leaks when the engine is actually running, and most of the time its running the oil is hot.
Originally Posted By: outoforder
Just had my car into the garage and I have a leak in the rear main seal. It is a small leak at the moment. I do want to invest much money into the car.
Well then, I'd pay the mechanic whatever he wants to charge you to replace that seal!
Just had my car into the garage and I have a leak in the rear main seal. It is a small leak at the moment. I do want to invest much money into the car.
Well then, I'd pay the mechanic whatever he wants to charge you to replace that seal!
Originally Posted By: outoforder
It's a 1997 Mercury Sable 3.0 12 valve
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
Try Maxlife semi syn 10W30 for a an OCI of 3K or so... If it is a slight oil leak, I would bet that it will slow down or even stop the leak. It could possibly take a couple OCI's before it works...
It's a 1997 Mercury Sable 3.0 12 valve
a 10w-30 high mileage oil vs. a thicker oil i.e. 15w40 or sae 30? Seems the consensus is for the high mileage
Try Maxlife semi syn 10W30 for a an OCI of 3K or so... If it is a slight oil leak, I would bet that it will slow down or even stop the leak. It could possibly take a couple OCI's before it works...
MMO, Rotella and AutoRX have each cured rear main leaks in the various vehicles I've owned. As long as the seal isn't cracked or crumbling it's probably leaking because it's hard and dirty.
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First it would be of the upmost importance to replace the seal that is leaking. If you don't, its just putting a band aid on the problem.
BUT since the economy is in the toilet and people are broke, then I can understand the band aid for now.
My friend had a car with a seal going bad, She has been using Valvoline HM in her car and the leak has completely stopped. Are all the HM Oils the same? Who knows, but I can vouch for the Valvoline did the job.
Good Luck.
Jeff
BUT since the economy is in the toilet and people are broke, then I can understand the band aid for now.
My friend had a car with a seal going bad, She has been using Valvoline HM in her car and the leak has completely stopped. Are all the HM Oils the same? Who knows, but I can vouch for the Valvoline did the job.
Good Luck.
Jeff
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I had a rear main that was leaking pretty good. I bought some of this http://www.usasealants.com/products/white-shepherd-oil-stop-leak-conditioner/ and it actually worked very well. Leak has completely stopped.
the 3.0 12v is the ole vulcan. a fairly bulletproof motor and unfortunately for you, one that needs to be pulled to get at the seal.
good news is you can get it out yourself in about 2 hours with common hand tools.
oh, and if this new to you, replace all the hoses and fittings for the coolant bypass system.
good news is you can get it out yourself in about 2 hours with common hand tools.
oh, and if this new to you, replace all the hoses and fittings for the coolant bypass system.
i have had a seeping rear main and use maxlife. after about 2000 miles it stopped seeeping. that was 2 years ago! mike
The rear main in the 3.0 V6 in my old Toyota 4Runner was leaking about a quarter-sized drop on my driveway every day for months. My friend, who was the lead mechanic for the local congressman's race team, told me to put 3 ounces of brake fluid in with my next oil change. I did that, within a week or so the oil spots got smaller, and within about 3 weeks the leak stopped completely, and it never leaked again up until the day I traded it about 6 months later.
Not advising anyone else do this, just throwing it out there......
Not advising anyone else do this, just throwing it out there......
Originally Posted By: quint
The rear main in the 3.0 V6 in my old Toyota 4Runner was leaking about a quarter-sized drop on my driveway every day for months. My friend, who was the lead mechanic for the local congressman's race team, told me to put 3 ounces of brake fluid in with my next oil change. I did that, within a week or so the oil spots got smaller, and within about 3 weeks the leak stopped completely, and it never leaked again up until the day I traded it about 6 months later.
Not advising anyone else do this, just throwing it out there......
Old trick. Most gasket and seal materials swell like CRAZY when exposed to DOT-3 brake fluid. A little might stop a leak, but every time you do it, you ultimately do a little damage to the gasket. Temporary fix at best.
The rear main in the 3.0 V6 in my old Toyota 4Runner was leaking about a quarter-sized drop on my driveway every day for months. My friend, who was the lead mechanic for the local congressman's race team, told me to put 3 ounces of brake fluid in with my next oil change. I did that, within a week or so the oil spots got smaller, and within about 3 weeks the leak stopped completely, and it never leaked again up until the day I traded it about 6 months later.
Not advising anyone else do this, just throwing it out there......
Old trick. Most gasket and seal materials swell like CRAZY when exposed to DOT-3 brake fluid. A little might stop a leak, but every time you do it, you ultimately do a little damage to the gasket. Temporary fix at best.
Valvoline maxlife has worked for me before, give it a shot. It may take a few oil changes for it to take effect.
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