Switched from mineral to fully synthetic oil! Problems ahead?

My new Nissan Sunny from 1992 has been using mineral oil. I recently purchased this old and well-kept Nissan and when the oil was changed, the new was fully synthetic. I know that it is generally not advised to do this, but when I went to buy the oil the dealer recommended the fully synthetic oil. He said he knew Nissan cars and said this would be good. I thought to myself, “Who am I to disagree?”.





Please note that I am aware that fully synthetic oil works better than mineral oil in cold temperatures. Where I live it gets regurlaly -15 Fahrenheit/-25 Celsius during the winters. This fact made me also to try the fully synthetic oil.





To the point, my questions are:


1. Did I do a terrible mistake by switching to fully synthetic oil? What risks may lie ahead?


2. In case I regret using fully synthetic oil, can I switch back to mineral oil? Or is to too late?


3. Please don’t tell me I have damaged my engine?





Experts! Share your knowledge!Switched from mineral to fully synthetic oil! Problems ahead?
No you did a good thing for your car,,probably one of the best things you could have done for it as switching it over,,and your not looking at any long term problems either,,i own a repair shop,,and switch high mileage vehicles over all the time,,and never had any problems with it,,you made a wise decision,,and don't let any body tell you that you have screwed up,,or something dumb like your going to need a new engine now,,if people who answer these questions would just try and learn about the things there answering,,instead of just trying to get the 2 points that you get from it,,there would be a lot more happy people out there,,i answer each question based on experience,,not from a answer i found on the Internet somewhere,,i hope this helps you,,you did OK.Switched from mineral to fully synthetic oil! Problems ahead?
You did a good thing by switching to Synthetic oil.


There is nothing wrong with it. I run it in my own vehicles, and they are my livelyhood.


Keep the weight of the oil the same as it was before.


-Do NOT- mix conventional oil with Synthetic oil.





The only factors to consider are:


Oil consumption before swap. Is the vehicle burning or leaking oil to the point that you have to add a quart before the regular oil change interval? If it has been well kept, then I see no future problems.
the only problem with switching to synthetic oil on a car from 1992 is that all of the seals and ports and gaskets have been coexisting with the slightly thicker conventional oil and have also became somewhat soiled and filled with deposits of debris that has settled throughout the years. when you switch, the synthetic cleans out the debris and exposes the seals and gaskets causing leakage from all sorts of places, including burning oil which is probably why your oil level is low . what I would suggest is swiching back to the origional oil type and changing it regularly I doubt you have caused anny real damaged.
You can switch no problems... it is just the old seals that the conventional was swelling and may have been covering up a leak or two, that synthetic will not. YOU CAN mix the two.... what is a syn blend anyway? (of course, not 50/50, probablly 10 percent syn at the least) And you can always switch back.......


The oil consumption you have may be a leaky seal (which did you notice any usage before this oil change with dino?) or its trying to clean the ring packs.