Please do not worry about using straight 30 weight...especially since you live in Phoenix. That is the single most important factor...at least in my opinion. If on the other hand you live in an area prone to cold weather (or even cold humid mornings) and if you drive a modern vehicle with notably different specifications than the 216, a multi-weight oil will be needed. However, you're not in that crowd at all. Your weather is warmer than Dallas and I use straight 30 weight and have since the early 1960s. The 216 or 235 in a warm to hot climate does just fine with a single weight oil. VR-1 30 weight is what I use. And with 30 weight you may have fewer oil seepage problems. As for frequency of oil changes, you have less relative humidity in Phoenix so you will be just fine with changing your oil once or twice a year (depending on mileage). My 2 cents worth. Good luck!
