[hank14]

The PO had been using regular unleaded in my 99 for over a year when I bought it in 2003. It had 116,000 miles on it. It seemed to run fine, but I did hear some pinging under load (pulling tree stumps) once, so I switched to premium (90 octane here) and some techron cleaner twice a year. As gas prices go up, the cost of premium, if it remains $.20 more than regular, gets proportionately less, if that matters. I just have to leave the beast home for most long trips until I can get it paid off.