Oil leak after switching to synthetic

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Its common with any higher mileage vehicle, to develop leaks after switching to synthetic. I'd just go back to dino oil.
 
Definitely not a myth, oil leaks after switching to synthetic on higher mileage engines are pretty common, fortunately its not a big deal. If you switch back to regular oil the leak will stop (assuming there was no leak with regular oil before). How big is the leak? if its just a few drops when the cruiser is parked overnight its really not a big deal. Do you know where the leak is coming from? The distributer O-ring is know to leak and its an easy fix, if its the rear main seal its a bit of a job to replace it. Switching back to regular is definitely the easiest route.
 
Landseer said:
Definitely not a myth, oil leaks after switching to synthetic on higher mileage engines are pretty common, fortunately its not a big deal. If you switch back to regular oil the leak will stop (assuming there was no leak with regular oil before). How big is the leak? if its just a few drops when the cruiser is parked overnight its really not a big deal. Do you know where the leak is coming from? The distributer O-ring is know to leak and its an easy fix, if its the rear main seal its a bit of a job to replace it. Switching back to regular is definitely the easiest route.
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As far as I can tell there were no oil leaks before switching to synthetic. The leak is coming from the rear. I notice it more when it sits for a while. My guess is the upper arch deal or the rear main seal.


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Either fix leak or switch back to Conventional.
If leak is only a few drips watch oil level and address later.
I can't stand leaving a puddle in some bodys drive when I visit, it's like peeing in their bushes, doesn't hurt much but annoying.
 
This happened to me too, but I stayed the course thinking the benefits out weighed the downside. A leak like this eventually needs to be addressed anyway. I use high mileage M1 and by oil change time, the seal swellers had time to work and it stopped. But at least I know where to keep an eye on.
 
Zimbwanabe said:
This happened to me too, but I stayed the course thinking the benefits out weighed the downside. A leak like this eventually needs to be addressed anyway. I use high mileage M1 and by oil change time, the seal swellers had time to work and it stopped. But at least I know where to keep an eye on.
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I used mobile super synthetic. Was the seal sweller something you added or just part of the high mileage oil?


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sbrodacz said:
I thought that was just a myth


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Supposedly, it's a myth, but it happened to our prius when we switched to synthetic. Allegedly it stops after a few months. I figure it's twice as bad with an 80.
 
That's strange. I had the complete opposite happen to me. Switched to Rotella T6 5w 40 and noticed easy a 50% decrees in my slow oil leak. It was always just a drop or two a day, but now it's like a drop or two a week. I changed out cardboard to track it. Anyways, that's my experience.
 
Aloha Jen said:
That's strange. I had the complete opposite happen to me. Switched to Rotella T6 5w 40 and noticed easy a 50% decrees in my slow oil leak. It was always just a drop or two a day, but now it's like a drop or two a week. I changed out cardboard to track it. Anyways, that's my experience.
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Maybe that had something to do with using rotella


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The majority of us have nothing to gain from synthetic oil as proven by many an engine gas and diesel operating for hundreds of thousands of miles on good dino oil. Drain it and refill with DEO 15/40 and have a happy, clean engine. The robust additive package in DEO is good for your cams too.
 
baldilocks said:
The majority of us have nothing to gain from synthetic oil as proven by many an engine gas and diesel operating for hundreds of thousands of miles on good dino oil. Drain it and refill with DEO 15/40 and have a happy, clean engine. The robust additive package in DEO is good for your cams too.
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See. I've been told not to go with 15/40 and to go with what toyota recommends.


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The swellers are part of the high mileage formula, or so I was told on Bob is the Oil guy. I don't know other than that and my experience. My Blasckstone reports suggested I change at 10k intervals but I still do every 3k or so. Cheap insurance to me. I love my 80.
 
Zimbwanabe said:
The swellers are part of the high mileage formula, or so I was told on Bob is the Oil guy. I don't know other than that and my experience. My Blasckstone reports suggested I change at 10k intervals but I still do every 3k or so. Cheap insurance to me. I love my 80.
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You're just using a high mileage mobile 10w 30?


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Go to bobistheoilguy.com and read about oil until you can't take it anymore. Many people run DEO in small engine too including motorcycles, lawn mowers,etc. it's more expensive because there is more in it. Guys will tell you that you don't need it just like I said we don't need synthetic. It's all about which price and which bottle you like most. Haha. DEO will not hurt but only help your engine. Hell, why not run a good 20/50 Dino oil? Toyota's recommendations for oil were driven by the EPA for fuel economy . I'd like a private meeting with them and the IRS....
 
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