I live and drive my 2008 Lexus RX350 in Santa Fe, NM, with elevation of 7,000 ft +. Is using premium gas, as requied by Lexus handbook, advisable or benificial at this elevation, or a waste of money?
At that elevation, you could probably drop down to the mid-grade gas with no problems. It might be too much of a stretch to switch to regular.
The octane rating in your area has already been adjusted for elevation. As an example, at sea level, the octane spread will look something like this- 87, 89, 91. At higher elevations, the octane spread will be 85, 87 and 89 for the various grades. Premium is premium and if it requires it, you’ll be better off using it.
Try a tank of regular…If you can detect no drop in performance or engine “ping” under acceleration, you can use regular safely. Damaging engine knock is not something that goes unnoticed…You WILL know if your engine demands premium fuel…The difference in performance between 85 octane and 89 octane is simply not enough to be paying .20 cents a gallon extra for it…Many, if not most, “premium fuel only” cars run just fine on regular and suffer no engine damage because of it…