Rear main oil leak. Will Lucas stop leak help?

carrotsnapper

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I have a 1995 Dodge Ram 1500 4X4. For a couple years now, there has been a slow drip behind the oil pan. Annoying! A guy told me to try some Lucas stop-leak. This is my tow vehicle and I don't drive it much. I've been told that to fix it I'll need to unbolt the tranny and slide it back enough to get to the seal. Now, to me, that is a little overwhelming. Will the Lucas stuff help or hinder? I've always understood that a stop leak isn't a good fix. Your thoughts?
 

Bob_VT

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Well ...... I have used stop leak products over the years in power steering, transmissions, radiators and they all had a temprary result and the leaks had to be fixed right. Give it a try in my opinion you will not loose ground and it may work.

For people with oil leaks my advice is to stay away from the synthetic oils and stay away from the "dura lube" type stuff. Those exotic oils will make the leak worse then the conventional oils.
 

David Young

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Yep. The stop leak stuff works, most of the time. It swells the gaskets. My friend had a automatic transmission with a bad leak, I told them to add a bottle of 'stop leak' to the transmission fluid. It worked for a little more than a year, until they totaled the car in a wreck :(
 

Sprig

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At best it's a short term fix. To avoid major problems in the future you need to get it repaired correctly.
 

robert graham

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I used the Lucas power steering stop leak and it definitely stopped the power steering gearbox from leaking for several years....gearbox finally got warn and just replaced it with a re-built unit....
 

WIMUSKY

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I tried Lucas on my GTO, never stopped the rear main leak...
 

Boomyal

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I tried Lucas on my GTO, never stopped the rear main leak...

I imagine that there is always a point beyond salvation but it sure does not hurt to try it. It is my understanding that the way those things work is that they make the seal material swell. A chemically swelled seal does not have the durability of the raw material and will eventually break down.
 

WIMUSKY

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I imagine that there is always a point beyond salvation but it sure does not hurt to try it. It is my understanding that the way those things work is that they make the seal material swell. A chemically swelled seal does not have the durability of the raw material and will eventually break down.


No doubt. It's worth a try.........
 

gm280

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carrotsnapper, Once a rear main starts to leak, there is only one sure way to stop it. Replace the rear main seal. I know that isn't what you want to hear, but that is the simple truth. Yes the tranny has to be either removed or slid back, if that is possible on your setup. But then you need to drop the oil pan as well. And it there isn't enough room, the engine will have to be lifted up. So while it isn't a simple job, it is not a hard job either. Just time consuming. BTDT
 

bigdee

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1. 21 years old
2. slow drip
It may make economic sense to just live with it. How often do you drive it? RMS only leaks when engine is running so adding a quart of oil now and then is not that much of an inconvenience. If you have a concrete floor just put a mat down. Sense stop leak eventually destroys the seal and rarely works anyway I would not use it.....maybe 15-40 rotella diesel oil instead.
 

WIMUSKY

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Just dawned on me I used Bars Leak for Rear Main Seals. Yep, they make one just for rear mains. So it's labeled.......
 

MTboatguy

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Marvel Mystery Oil can do wonders for leaks, I have used it many times over the years in various old cars that developed small leaks.
 

bruceb58

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I would just replace the rear seal. Stop leaks are bad news for every other seal and gasket in your engine. It's a solvent that softens and swells up your seal. You really want to be putting that in your engine?

And no, there is nothing you can put in that just affects the rear oil seal.
 

WIMUSKY

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I would just replace the rear seal. Stop leaks are bad news for every other seal and gasket in your engine. It's a solvent that softens and swells up your seal. You really want to be putting that in your engine?

And no, there is nothing you can put in that just affects the rear oil seal.


Like the additive tells itself, "I'm heading straight to the rear main and by-passing the other seals"....... Silly.....
 

bruceb58

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Like the additive tells itself, "I'm heading straight to the rear main and by-passing the other seals"....... Silly.....
Hey..but people buy these snake oils so they are used to marketing to these type of people.
 

Scott Danforth

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Take a diaper, fold it in half, smash it up in the area between the oil pan and the transmission shield. Use duct tape or zip ties to secure in place.

Diaper will hold almost half a quart of oil, and keep it from marking its spot. Not a permanent fix, however a band aid. Worked on many of my beaters
 

flipbro

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High millage oil has an additive to help condition seals. When you change your oil next try a high miliage motor oil like deffy..
 

bigdee

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Take a diaper, fold it in half, smash it up in the area between the oil pan and the transmission shield. Use duct tape or zip ties to secure in place.

Diaper will hold almost half a quart of oil, and keep it from marking its spot. Not a permanent fix, however a band aid. Worked on many of my beaters

^^^x2^^^ never heard of that but I like it. Makes more sense to me than spending a thousand +dollars on a 21 year old part time vehicle.
 
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