is it true?

is it true once you use synthetic oil you cant go back to regular motor oil because your engine is use to it? thats what someone told me at a parts store, just wanted to varify.

thanks

I had a Jiffy Lube tech tell me the same thing. :)

did you asked why is that?

so what happens if you buy a car at an auction, and you dont know the history of the oil used? come on!!! :screwy:

did you asked why is that?

Nope, because I didn't accept his story and felt he was trying to push a more expensive option, just as they do with the 75k oil that costs $10 more than regular oil.

there is no harm in switching...as long as what you are switching back to at least meets the oem specs. however fully syn oil keeps the engine lubricated alot better under certain driving conditions over regular. it doesn't break down as easily as regular oil would. but if you are just using your car as a daily driver and keep up w/ it's oil changes you should be fine.

Ive switch back n fort usin syn then reg oil. They only thing I notice is that my vavle train is not as noisy when I use syn(Valvoline). In my opinion, if u aint racin or drivin where yur engine runs real hot all the time, you dont need syn.

Synthetic oil permeates the walls of the cylinder to provide excellent lubrication. If you go back to standard oil after using synthetic, the smaller molecules in standard oil will literally slip by the rings because the synthetic oil has already become embedded in the cylinder wall. This will cause your engine to smoke like crazy.

And that's Why!!!

I have a friend who works for ford he help design the a/c unit and how it would affect the engine power when swithced on...he has a chemical engineering degree and a masters in mechanical engineerig ...he told me that if you use synthetic in a vechicle listed for non synthetic oil such as the honda accord..your gaskets can become worn after time and leakage can and will occur...i still use full synthetic ahahahaha....

oh yea he help design that on the new ford 500 and he also designed the transmission on the new t-birds and he helped with the new ford trucks he designed the insulation..that is why they are the quietest truck ever...

Synthetic oil permeates the walls of the cylinder to provide excellent lubrication. If you go back to standard oil after using synthetic, the smaller molecules in standard oil will literally slip by the rings because the synthetic oil has already become embedded in the cylinder wall. This will cause your engine to smoke like crazy.

And that's Why!!!




What you said is totally bullsxxt.

The rumor I've heard is that synthetics have additives that expand your seals...when you switch back to regular oil, the seals can shrink and cause leaks...I think this is BS, there have been a few threads in the Technical section of AF regarding this subject though...so if you want to read their opinions, I suggest you do a search.

What you said is totally bullsxxt.

What he said is all true.

:iagree: very true indeed