Lexus ES - Is premium gas a must?

ptguard1

I've read conflicting reports as to the need to use premium gas 100% of the time. Some have said they use regular & only use premium about 1 out of 4 fillups. Opinions?

quanoname

I wonder that myself too?
Just took delivery of my '10 ES350 and gas is running low.
The book call for premium gas and i was wonder will this car drink regular or 89?!

lexpaul

The question of the necessity of using premium fuel in the ES has been hotly debated in Lexus forums. There was one member who did a little research and found that the use of low grade fuel over time will slowly degrade engine performance. You may not notice any difference initially but over a period time you will develop sluggish engine performance and could void your warranty. Low grade fuel (87 or 89) is allowed in the owners manual, but it is not 'recommended' as the fuel that should be used constantly, only use it if 91 or above octane is not available at the time of fill up. Hope this helps.

kenb757

This was debated many times already (see the Avalon vs. ES350 blog: tjc78, "Toyota Avalon Limited vs. Lexus ES 350 Comparison" #146, 16 Sep 2008 11:42 am). The engine in the ES is the same one as in the Avalon. The slight torque and horsepower advantage in the ES is solely due to the use of premium fuel. Most engines today are perfectly capable of running on regular fuel because of knock sensors which send a signal to the ECM to retard the ignition timing if pinging is detected. I would be loathe to spend an extra 30-40 cents a gallon on premium. My Northstar equipped Lucerne Super gets along just fine on regular, as did my DTS previously. It might lose a 3-4 horsepower, but it's not missed unless you're participating in time trials or a race.