Originally Posted By: Eddie
A question for those who state drain intervals. What is your criteria for short, medium and long drain intervals? In addition; please point us to the UOAs to back up the statements that Valvoline is not good for xxx intervals. Thanks.. Ed
Well, I have reviewed all of the Valvoline UOAs I have been able to find in that forum, including a recent one of Maxlife SB in a Tahoe (I think), and those that included TBN showed that Valvoline products appear to be good for around 6-7K.
Those UOAs are as available to any member as they are to me.
This does not disturb me, since I normally run 5-6K OCIs, and the Valvoline UOAs usually show very low metal levels in the used oil.
I would consider 4K or less to be short, 5-7K moderate, and anything over 10K to be a long interval.
I don't think Synpower, much less VWB, can retain TBN for 10K in most engines, but I'm open to being proven wrong.