I've decided I want to run synthetic in my Scion. I'd also like to stick with one brand. Anyways, I've been running Valvoline products in our vehicles lately, mostly because of the great wear numbers I've seen in several UOA's. I'm going to change every 5,000miles due to the warranty, and while I know its overkill, its not really that much more money every oil change in the grand skeem of things. Synpower sound like an ok oil to use for 5,000miles? I know it doesn't seem to have the TBN retention of other synthetics, but I figure it would be ok for a 5,000mile oci. I might try the new Mazda GF-5 0w20 and maybe even the toyota 0w20 first just to see if the high levels of moly in those oils quiet down the slight piston slap my engine has, but I have my doubts it will. What do you guys think?