Not sure if this has been asked but does anyone know where the myth you can't switch between synthetic and conventional started? I still have some old school minded people (Dad) who still think once they go synthetic they can never go back to dino. Was there actual truth to this in the early days of synthetic or has it always been a myth?
Synthetic to Conventional Switch Myth
- Thread starter AIRJAC3
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It's always been your vehicle and your money, to spend on what you want. The oil companies only want you to buy their most expensive oil, which is almost always synthetic.There's no proof changing back and forth hurts anything.,,,
I asked Blackstone if there were any issues with partial blends of Chevron Delo 400 15w40 and Chevron 5w40 synthetic, and they said no problem at all.
I don't think it's any different from changing oil weights or brands.
I don't think it's any different from changing oil weights or brands.
wemay
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Not sure where it started but if you visit the websites of any of the major brands, they will clearly state switching back and forth is no issue.
The last time I took my Subaru to the selling dealer for an oil change-I decided that I no longer wanted the (optional for my year/model) synthetic oil change. The Service Advisor insisted that I couldn't switch back. After I told him just put conventional in they did so.
I haven't been back to that dealer since.
I haven't been back to that dealer since.
I think the myth came about when there were "synthetic" oils which weren't really synthetic oil as we know it today, but just rando chemicals more like oil additives.
And once you switched to those random chemicals you couldn't switch back due to incompatibility.
And once you switched to those random chemicals you couldn't switch back due to incompatibility.
The myth got its inertia from the fabled "ultra cleaning power" from the original synthetics (which might be their own myths).
Just go to whichever you want whenever you want. So, so much of it comes from oil (dead dinosaurs) in the first place.
It's all good. Except for the cheap stuff. Kira
Just go to whichever you want whenever you want. So, so much of it comes from oil (dead dinosaurs) in the first place.
It's all good. Except for the cheap stuff. Kira
It's funny because I've tried to convince people that there really is no taboo in switching back and forth but some are just too hard-headed I guess. I think I went one time from Super Tech Conventional to Royal Purple then Castrol High Mileage in my old 96 Mustang GT I had. Car didn't blow up, and if it wasn't for the clutch that car would still be running strong in my driveway today.
I guess it's the same for people that still believe in the 3,000 mile oil change. Old habits die hard.
I guess it's the same for people that still believe in the 3,000 mile oil change. Old habits die hard.
I've read at least a few times over the years that early synthetics were esters which caused a lot of swell in gasket materials used at that time. Switching back to less polar mineral oil caused the seals to shrink and leak. Not really an issue with today's group III and IV oils (i.e. Synthetics)
I used to alternate both..never an issue. Syn in winter dino in summer..past few years ive stuck with syn.
The myth goes back at least to a certain pioneer in synthetic oil marketing, Amsoil. I still have a 1980's Amsoil oil flush quart can (the kind you have to stick a spout into). They pushed that "you have to get all that oil Dino oil out" thing hard, and of course they had an engine flush product to sell you to make a few more bucks off the deal.
Maybe the myth predates Amsoil, but they are very responsible for making the myth flourish.
Maybe the myth predates Amsoil, but they are very responsible for making the myth flourish.
A few folks had the dreaded synthetic leak syndrome on engines with worn seals that started to leak on syn. So they assumed that one was not compatible with the other and had to be kept separate ...
Then the refiners started selling syn-blends and that sort of took the air out of that argument
Then the refiners started selling syn-blends and that sort of took the air out of that argument
Originally Posted By: AIRJAC3
Not sure if this has been asked but does anyone know where the myth you can't switch between synthetic and conventional started? I still have some old school minded people (Dad) who still think once they go synthetic they can never go back to dino. Was there actual truth to this in the early days of synthetic or has it always been a myth?
If you have an old engine that has some degree of sludge and was run on a low detergent dinosaur base oil and change to a bling bling modern high tech full synthetic (The GTL or German standard group 4 synthoils are slightly better if you have a turbo charged engine), there is a risk that the oil consumption or leak rate will increase.
The reason a FS or one with a lot of detergents can increase oil consumption is due to what is called the false oil seal effect, where sludge and varnish are helping worn or split oil seals function. The problem is even more significant with bad gaskets, as the only thing holding the gasket together might be sludge.
My advice is that if you want to switch an engine with a high oil consumption to a FS oil, add half a can of Liqui Moly Motor Oil Saver or other major brand stop leak additive.
Going back to dino is not an issue, although I would not use an non FS oil in a turbo charged engine if you want it to last as long as possible. Also you might need to reduce the OCI in some cases, particularly if the engine type tends to shear it's oil as many bike and turbo engines do.
Not sure if this has been asked but does anyone know where the myth you can't switch between synthetic and conventional started? I still have some old school minded people (Dad) who still think once they go synthetic they can never go back to dino. Was there actual truth to this in the early days of synthetic or has it always been a myth?
If you have an old engine that has some degree of sludge and was run on a low detergent dinosaur base oil and change to a bling bling modern high tech full synthetic (The GTL or German standard group 4 synthoils are slightly better if you have a turbo charged engine), there is a risk that the oil consumption or leak rate will increase.
The reason a FS or one with a lot of detergents can increase oil consumption is due to what is called the false oil seal effect, where sludge and varnish are helping worn or split oil seals function. The problem is even more significant with bad gaskets, as the only thing holding the gasket together might be sludge.
My advice is that if you want to switch an engine with a high oil consumption to a FS oil, add half a can of Liqui Moly Motor Oil Saver or other major brand stop leak additive.
Going back to dino is not an issue, although I would not use an non FS oil in a turbo charged engine if you want it to last as long as possible. Also you might need to reduce the OCI in some cases, particularly if the engine type tends to shear it's oil as many bike and turbo engines do.
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Originally Posted By: HangFire
The myth goes back at least to a certain pioneer in synthetic oil marketing, Amsoil. I still have a 1980's Amsoil oil flush quart can (the kind you have to stick a spout into). They pushed that "you have to get all that oil Dino oil out" thing hard, and of course they had an engine flush product to sell you to make a few more bucks off the deal.
Maybe the myth predates Amsoil, but they are very responsible for making the myth flourish.
Yes, but in Amsoil's Q&A, and tech service since day one, have always said you can switch back and forth, no problem. Amsoil flush and getting the "dino" out was about extended drain and starting with a clean engine.
My opinion is that it just another one of those corny old oil myths based on ignorance more than anything.
The myth goes back at least to a certain pioneer in synthetic oil marketing, Amsoil. I still have a 1980's Amsoil oil flush quart can (the kind you have to stick a spout into). They pushed that "you have to get all that oil Dino oil out" thing hard, and of course they had an engine flush product to sell you to make a few more bucks off the deal.
Maybe the myth predates Amsoil, but they are very responsible for making the myth flourish.
Yes, but in Amsoil's Q&A, and tech service since day one, have always said you can switch back and forth, no problem. Amsoil flush and getting the "dino" out was about extended drain and starting with a clean engine.
My opinion is that it just another one of those corny old oil myths based on ignorance more than anything.
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