[obbop]

If your machine operates in severe climates such as 20 below zero winters and regular 100 degree plus summers I would consider a synthetic oil.

Though the change interval can be extended I would be leery of going too long due to contaminants from combustion, etc.

If you stick to a 3,000 or 4,000 mile oil change interval I believe a good quality regular oil will perform well.

Some folks pay for oil tests to determine the amount of suspended contaminants thus allowing them to determine an optimal oil change interval.

Being a wee bit cheap I have decided to stick to a 3,000 to 3,500 mile oil change interval using good standard non-synthetic oil.

The debate about the best oil filters is ongoing but I decided the AC Delco filters will do as well as most and better than some.