I bought my truck from an idiot that used Penzoil and some white, non labeled junk filters. I switched it over at 114K. i'm at 121K. NO problems yet. You are right that it seemed to be burnin oil... i had to add 1qt over 10K miles and it got BLACK and I mean FAST! I just did my 2nd Amsoil oil change and it's still pretty clean 1K later.

I did some math too.. 3K change with filter and wanted to know what would be an = $/mile... and got about 6,600 miles. So all you have to do is run 6,600 miles and it's the SAME PRICE as Dino! (6.99/qt+toyota filter+7% tax) Vs (1.88/qt+toyota filter+7%tax) I'll change it about every 7K, save some $$.