sderman

I know this has been talked to death, but I am interested in the long-term experiences of any owners who have used regular grade gas in their RXs. I am about to sell my '07 with just over 50,000 miles to a friend for his son. I have always used premium grade gas from a top tier supplier (usually Mobil-Exxon). But should my friend or his son ask for my opinion about using far cheaper regular grade fuel I would like to be able to mention the long-term experiences of those who have used only regular grade fuel in their vehicles. Please respond. Thanks.

DennisMik

Got my first Lexus in Jan 2014. I now have 2. Since I have owned them, I have used regular grade gasoline with out any drivability issues. As a similar statement, all the cars I have owned since the mid 1990's (4 of them) which claimed to require premium also ran fine on regular.

I have put an occasional tank of premium in and can detect a small performance boost, but it is not very much. Besides, the car's computer with all its sensors will adjust the timing and fuel injectors to work just fine with regular.

kickin8

iTrader: (1)

The computer is smart enough to know you have regular gas therefore retard the firing ... you will lose power vs premium gas and also cause more carbon deposits in the long run

DennisMik

I haven't had a problem with carbon buildup in 20+ years of running regular. Drove as part of the job, 30 to 40k miles a year. The only thing I can say is that those cars were not Toyota/Lexus.

sderman

I would certainly expect you would lose power using regular since the timing is retarded (most would agree that a minor loss in power is a small price to pay for fuel that is 20-30% cheaper). But do you have evidence that Lexus engines designed for premium but run on regular develop deposits or are your remarks based on theory regarding non-optimal combustion? This is why I would like to hear from owners who have been regularly running regular for these past 10 or so years. More importantly, I would like to hear from owners who have run their cars for many years on regular gas from "Top Tier" suppliers (as currently recommended by Lexus) since these suppliers state that their gasoline have sufficient additives in all of their grades to take proper care of our engines.

DennisMik

To add another 2 cents to this thread, I have always searched out the cheapest gas around. I have never had any problems with the engine running on the gas I use. So if the cheap stuff works, I would be quite shocked if the "Top Tier" brands caused problems.

RX3302004

Cheap gas here too.

cdnewton

Previously, had a 1999 Lexus ES300 with 125,000 miles (traded) and 2004 Lexus RX330 with 212,000 miles (current). Run Sam's Club 85 octane (in Colorado).

On this forum, was warned of
-noticeable power loss
-catalytic converter damage
-knocking and/or pinging.

There may be some power loss due to the timing adjustment, but it isn't something we notice nor have we noticed any other issues. Our RX runs great but as always, YMMV.