Originally Posted By: btanchors
No, I don't work for Blackstone, LOL. But based on what I have learned I have cut the number of UOAs in half. I used to do oil change intervals at 5K miles, since the vehicle was under warranty. Now that it's not, I change oil at 10K miles or 1 year, whichever happens first, in all my vehicles. I pull a sample for analysis right before changing, so now I am doing one engine UOA each vehicle per year, which I think is reasonable. It's certainly a lot fewer than I was doing at 5K intervals!
That's good. Being a member of this site, I've also learned to stretch out the OCI. I have a 98 Sienna 3.0L (aka the sludger). Right now I have 7400 km on the OCI (approx 4500 Mi). I also change the oil filter every other oil change.
Regards, JC.