JD L111 with a B&S 20HP twin which has oil filter and oil pump. Presently using PP 10w30. Would there be any benefit to switching to Rotella T6 5w40? I have a small yard here in Florida and engines see only 45 minutes running per mowing. Ed
JimPghPA said:While the shearing is true, also consider that 15w40 is conventional oils and 5w40 are synthetics. They both may have the same amount of VII's and therefore there tendency to shearing would be the same. If you want to go synthetic, then T6 5w40 or Mobil 1 15w50 are both good choices.