onepercent

The recommended fuel for 4th gen GS 350 is 91 octane. Basically ES 350 has a similar V6 except it is detuned to have slightly lower output power. The recommended fuel for ES 350 is 87 octane. I wonder whether using 87 octane on a GS 350 would do any harm to the engine besides having lower performance.

bclexus

You have purchased a luxury vehicle that the car maker recommends 91 octane or higher. Does the savings of using 87 octane mean that much to you?

Pump whatever gasoline you wish as long as it is Tier 1. Vehicles nowadays have sensors that prevent spark knocking if the octane is too low. Some regular (87 octane) gasoline might not have the detergents that the higher octane gasoline has.

bclexus

If you are in the state of California, Ohio, Illinois, South Carolina or Tennessee expect your gasoline prices starting in July to reflect an increase due to increased taxes per gallon.

► https://www.foxbusiness.com/personal...s-to-rise-july

Cliffj

There is an interesting article in the July edition of Car And Driver on page 51 of the paper version. The article is entitled "Should you be buying premium?". The article states that octane rating does not change the energy content of a gallon of gas, but indicates only the resistance to knock. If you use a TopTier brand, all grades of fuel are supposed to have the same level of detergents. Most modern engines can run either grade without "harming" the engine. You "may" lose some power/torque, but may not notice it in real-world conditions. For instance, the Dodge Charger, with 5.7 hemi, produced the same 0-60 time & within 1/10 sec on 1/4 mile run between 87 or 91 octane. The article also compares a Ford F150 with 3.5L V6 turbo, Honda CR-V 1.5L inline 4 turbo, BMW 4.4L V8 Turbo and the lone non-turbo Dodge Charger. Just a data point, my wife has 101K on a non-turbo V8 (non-Lexus) and has only run 87 octane, because the salesman said it was okay. The manual says 89 preferred, 87 acceptable. She has never had an engine issue. A friend with the same V8 has over 200K using only 87 octane. Again, he has experience no engine issues.

charley95

I'm in Illinois and just filled mine up. The revenue is supposed to go to our failing infrastructure in which will be squandered again. Our newly elected governor just spent a 170 mil.of his own $$ on his campaign. He is quite hated in our state.

onepercent

Could you help me understand what top tier brands are? Is Costco brand in this top tier category?

imjohnphan

In all my Lexus' for their entire life has run 87 octane. (2GS, 3GS, 4GS and ES) none have given any problems related to fuel. I thought the 4GS was giving problems but figured out it was something else. All cars above 120K miles with the 2GS at 250K miles. So I could say its pretty safe.

It may not seem like a lot of money saved per pump, like maybe $5 at a time, but over the course of the mileage I put on these cars I could definitely say it added up.

bclexus

Yes, Costco's gasoline is rated Top Tier.

► https://toptiergas.com/licensed-brands/