oil question...
11-12-2010, 12:51 PM
#1
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oil question... Hi, I was wondering if anyone knows for sure why you are not supposed to go back to running normal motor oil after you have run synthetic. Why is it that once you run sythentic you are supposed to stick with it forever? Thanks
11-12-2010, 01:18 PM
#2
Sounds like BS, never heard of that one.
Always heard it the other way around because synthetic cleans up deposits left from conventional that "hide" leaks with gunk. So supposedly if you switch to syn then the leaks start.
I believe that is also a myth, but if not I'd rather fix the leaks than use oil that lets the gunk stay there.
Aside from that, I use synthetic anyway...not that much more expensive since you can always catch a brand on sale and you can run it longer. I normally go 6-7000 miles on an oil change with a good syn and a good filter.
Always heard it the other way around because synthetic cleans up deposits left from conventional that "hide" leaks with gunk. So supposedly if you switch to syn then the leaks start.
I believe that is also a myth, but if not I'd rather fix the leaks than use oil that lets the gunk stay there.
Aside from that, I use synthetic anyway...not that much more expensive since you can always catch a brand on sale and you can run it longer. I normally go 6-7000 miles on an oil change with a good syn and a good filter.
11-12-2010, 01:20 PM
#3
http://www.texlube.com/oilmyths.htm
Myth #4 - Once you start using synthetic motor oil you cannot go back to conventional oil.
Synthetic and conventional engine oils can't be mixed, or else they react and cause engine problems.
Fact: As long as the synthetic motor oil product and conventional motor oil product meet the viscosity and performance requirements outlined in the vehicle’s owner’s manual, you may interchange them with each other.
#6 Though I will say when building a new motor, I will still break in on SAE straight weight since I don't have access to the same stuff factories use.
But a good read regardless.
Myth #4 - Once you start using synthetic motor oil you cannot go back to conventional oil.
Synthetic and conventional engine oils can't be mixed, or else they react and cause engine problems.
Fact: As long as the synthetic motor oil product and conventional motor oil product meet the viscosity and performance requirements outlined in the vehicle’s owner’s manual, you may interchange them with each other.
#6 Though I will say when building a new motor, I will still break in on SAE straight weight since I don't have access to the same stuff factories use.
But a good read regardless.
11-12-2010, 01:50 PM
#5
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Who ever started this stupid rumor? You can switch back and forth with every oil change if you want. This is nothing new.
11-12-2010, 02:48 PM
#6
The only thing is that on a high mileage motor leaks can appear when switching TO synthetic, as conventional oil has larger molecules and can cause seals to swell. Otherwise, switching around is just fine, just if any leaks appear when switching TO synthetic it usually fixed it when you switch back to conventional.
