Well, for 75% of cars on FSS systems the oil change interval of 12K miles will work out just fine. BUT for the rest of those cars following that schedule leads to SLUDGE.

Have seen cars with "perfect FSS" service history & an engine that was so sludged that you wouldn't want it. SOME need complete disassembly.

If you drive in a metro area FSS doesn't suggest for oil changes soon enough.

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