Originally Posted By: ridgerunner
Even Amsoill SS says to replace once per yr.
Yes, it does.
https://www.amsoil.com/lit/databulletins/g2880.pdf Page 4 of 4 SERVICE LIFE Normal Service – Up to 25,000 miles, 700 hours of operation or one year, whichever comes first, in personal vehicles not operating under severe service.
But if you dig a little deeper and send in UOA, Horizon Test Lab (Amsoil) does not even ask for an initial sample until 7500 miles.
I've been sending them oil samples for many years; and I'll tell you that engineers have two favorite words: Depends and Perhaps. Depends upon the vehicle, storage conditions, driving conditions, etc. Anything that anyone says is nothing but speculation until an oil analysis is done. My two cents as to what the OP should do is send in an oil sample for analyzation and make an informed decision. Need not do this every oil change, but you're attempting to set precedent. If memory serves me correctly (which it often does
NOT there is a user on here (A310 or Crusher) that has about 75K on Amsoil SS [with bypass oil filtration]). I've only run Amsoil out to 37+K;
with supporting UOA.
Of course, you can always change it however often lets you sleep at night. Why not throw good oil away? Go for it, keeps the economy going and BITOG runs on speculation.