Dear Ray & Tom
I live on Okinawa and I own a Toyota Celsior (Lexus LS430) and so does my friend. We were discussing the best Gas for this car. We both work for the Military and the Gas on base is suppose to be 93 Octane. I believe that this is Mid Grad. Even though the gas is quite expensive on base, off base is quite a bit higher but they do sell High Octane. Our question is should we just continue burninf this mid grade or will it cause harm to the 4.3 litre V-8. My Celsior has 84,000 Kilometers on it (52,080 miles) not alot for a 7 year old car. I bought it when it was 3 years old and it only had 10,500 miles on it. It was driven by a lady to and from her work. Yeah I know, the dealer told me that to sell me the car. The truth is I met the previous owner when she was turning in the car and low and behold it was the truth.
Two questions. One: what does your Lexus require, per the owner’s manual, in terms of octane? Two, are you suffering any performance problems from the gas from on post?
Not sure why you think it is mid-grade; the PX system (AAFES or Navy) buys from a reputable local supplier (especially in Okinawa, where the fuel suppliers are limited compared to stateside), wherever the location, so unless someone has actually done a test, the mid-grade disguised as 93 octane sounds like a rumor.
Let me add an additional question or two. What method of measuring is the owner’s manual recommendations based on, and what method of measuring is the base and the local supplies based on. There are different methods and you may need to adjust to get a level playing field. The methods are call Manufacturers (M), Research ®, or a combination (M&R).
I doubt if you will have any problems or need for more than the 93, but do the checking to be sure.
As JEM said, pay attention to the method used for measuring octane as posted on the pump, and as specified by the manufacturer. Different methods give different octanes for the same gas in different countries. I wouldn’t be surprised if gas sold on-base is measured by US methods (do they sell it by the gallon?). If the car was built to be sold in Okinawa (a Japanese possession), it and off-base gas pumps ought to be talking the same octane method. If that’s the case, and on-base pumps are standard US method, you’ll have to ask around for a conversion between the two.