Until you send me samples of your oil at 1000 mile intervals for Brookfield viscometer measurements (measures viscosity)at various shear rates and temperatures, no one is able to put data behind the 3k vs 5k argument.
Data or no data, I can assure your the oil has more viscosity @ 3k miles than at 5k miles. Better safe than sorry.
Recursively Yours, Kenny... PETZ Member #5
SteamyZ. Never had did me wrong. - SL103 07/06/04 11:58:15