What is the best oil change interval for a Focus SVT using Mobil 1 full synthetic?
The best oil change interval is the one specified in the owner’s manual. The manual was written by the SVT engineers who built the engine. They know, better than anyone, how often the oil should be changed.
…and be sure to look at the “Severe Service” maintenance schedule, which specifies oil changes much more often than the regular maintenance schedule. Also, read the definitions of “Severe Service”. After you read those definitions, you will see why a substantial portion of the cars on the road actually fall into that category, and if the regular schedule is used on those cars, they are not being maintained properly.
If you want to extend the oil change interval by using a higher quality oil than specified, you need to do oil analysis. YOu can mail off a sample of oil to do that.
The best oil change interval is the one listed in your owner’s manual. I don’t recommend you extend it regardless of the type of oil you use.
The best thing you can do for this car is maintain it according to Ford’s recommendations using an oil that meets the specifications listed in your owner’s manual.