How long can you avoid changing full synthetic oil

[jtsanders]

Oil change interval cannot be extended just because you switch to synthetic oil. The amount of additives in the oil determine when the oil begins to break down in normal driving conditions. Synthetic oil might have more buffering additives, but it doesn’t have to have more than typical mineral oils. Synthetic oils stand up better to high temperatures, and in that sense it resists break down. If you don’t use the car much, just use mineral oil of the correct grade. Mineral oil has been used for decades without problems. I see no need to spend extra just because you can.