Ralph,

10,000 miles oil and filter changes for a 617? Certainly.

Although I have not done an oil analysis, others have on 10,000 mile oil from 617 engines which show there was no problem using oil synthetic that long.

Let it be known that this car is used mostly for long trips and almost always gets the oil up to operating temperature each time it is started. For many short trips and city driving, 10,000 mile oil and filter changes might not apply.

P E H