USING ARCO REGULAR: Bought my 92 LS 400 3 years ago [Aug 01] with 145K miles on it and put 15K miles a year of 50-50 freeway-town driving in the San Francisco Bay Area. At the recommendation of Lexus dealer Service Mgr. used Chevron mid grade 89 octane gas containing Techrolene and experienced no knocks, though he personally uses premium. When gas prices soared two years ago, switched to Arco regular [87 octane] and waited for the expected ping and nothing. Not once in two years has it ever pinged like 91 owners have told me.
Having read all postings on this subject, including USA Today article, I'll take my chances on carbon buildup and not interested in more power or increased acceleration. Like other happy Lexus owners, expect to get at least 300K miles before trading off probably for a 93-94. Dislike Generation II's and hate III's.
Anyway, if I don't get 300K will be disapponted, will post mileage results on this site, and the premium club will have a new member. Until then, agree with one owner who uses regular around town and premium for long trips through the mountains.
My 5,000 mile maintenance schedule is simple: Toyota oil/filter change using Chevron 5-30 oil purchased by me as recommended in owner's manual since Toyota uses 10-30 in our area; Big O Tire rotatation; and 12 ounces of Chevron Techroline into the gas tank to keep fuel injectors clean.
At 200,000 mile service, will have timing belt, water pump, and whatever else is included in this package at my independent Lexus repair who uses all OEM parts [$600-700], and maybe fuel pump and fuel filter depending on what he says. The latter two items are on my agenda thanks to Lexus Owners Club.
Just calculated 10 months of gas mileage using ARCO regular 87 octane exclusively [Jan 04-Oct 04] at 19.8 mpg. Lowest was 15.9 in June [hot weather] and 24.1 in January. Without A/C, typical town/highway mileage is consistently 20 mpg ranging between 19-21. With a Lexus mpg rating of 18 town-23 highway, 20 mpg sounds good to me for the San Francisco Bay Area.
How are you doing?