Currently running Penrite HPR 5 (5W-40) changed every 5,000k or 6 months. I always figured changing oil often was a good "insurance" on the engine.
Anyone using Royal Purple?? Been thinking about this stuff after reading some positive articles testing wear rates.
Coyote are you testing your oil? Just googled these guys http://www.oilcheck.com.au/index.html and they appear to charge $43 for a basic spectrum analysis. Anyone better out there to use??