hearnje

Has anyone used the new Mobil 1 Syntech 0W-40? Does anyone feel that that far of a strech over grades may not make a great oil?

Aldous

That's what I'm running.

DLow

0w40 Mobil 1 - The 'stretch' isn't too hard for a synthetic oil

captainbilly

Synthetic oils get their multi weight characteristics in a completely different way than conventional oils. Conventional oils must use additives, which break down over time, to get wide viscosity ranges. Synthetic oils are "designed" to have the multi viscosity characteristics in the base oil and the characteristics don't change much over very long periods of time.

Synthetic oil manufactures used to recommend very long oil change intervals (40,000 miles) because the oil can easily last this long. The problem was that the additives, like corosion inhibiters, did not last as long as the base oil so they now generally recommend normal oil change intervals.