Would a one time oil change to synthetic oil benefit the engine at all? Not sure I want to open that can of worms, what do you think?
Thanks
Dan

Thanks for the replies, the engine through the oil filler cap looks very good it has received regular oil changes in the 10 years I owned it. The car was in very good condition when I bought it so I suspect it was reasonably well cared for in the first 10 years also.

My biggest concern is starting an oil leak in the rear main seal although at 220 k miles a clutch is probably coming up sooner than later.

Dan

Hello,

Yes it would benefit the engine. That's for sure. It would clean some gunk out. But the degree of cleaning depends of the baseline state of gunk in the engine. You may have to keep using synthetic 2 to 3 more oil changes to fully reap its benefits.

I think MMO has better gunk cleaning property. Had used once. Poured half a bottle into crankcase and left it there till next oil change.

On the other hand synthetic oil is best to prevent gunk from happening in the first place, as compared to cleaning them out (i.e. have to use them all the time).

Regards,
Amarin.

I've heard of some people running Mobile 1 between conventional oil changes to clean out the engine. Others always run synthetic like me. With older engines, it may clean out gunk that has plugged up small gaps in the seals, which could cause oil leaks.

From what I've read, synthetic doesn't sludge as easily as regular oil so you can go a bit longer between changes. I use a bio-based synthetic that's environmentally friendly and my engine seems clean and happy.