Hello Scotty,
My father is a mechanic of hot rods for over 60 years and he says that once an engine has had synthetic oil in it you cannot go back to conventional.
I recently bought a 2012 Ford Focus SE (45,000 miles and automatic) and it says that it should be using conventional 5w-20 oil.
I have a couple questions regarding this.
1. Can you switch back and forth between sythentic and conventional oil? (The only reason would be if the previous owner used sythentic)
2. If someone before me put sythentic oil in the engine can I go back to conventional?
3. On a 2012 Ford Focus SE with 45,000 miles, is there any reason to switch to sythentic for the future? I plan on keeping this vehicle for many years.
Thank you for all your videos especially the one about buying used cars from a dealership and the extended warranty policies.
Thanks for the help,
Marycolleen
You do not want to go back and forth between oil types. If the vehicle has had synthetic its whole life, you want to continue to use synthetic. Switching from conventional to synthetic also causes issues, mostly new leaks you may not have had with conventional oil.
Synthetic is better lubrication for cold starts, and even more so in cold climates.
I remember changing oil in an old 305 Chevy. It was the dead of Winter here in Michigan. Temps in the single digits. I went from conventional 10W-30 to Mobil1 10W-30. The next morning, that car turned over like a Summer day. The lack of usual ticking, clicking and whining from the engine on that cold start made me a believer.
