Statman

Actually 87 can be used in a pinch.

hadokenuh

I see "What gas to use" threads on every single car forum.

Just follow the recommendations in the manual and sleep better at night.

If you are convinced to use anything lessor, just use it. But when you sell your car, please be honest and say "I've been using xyz gas for the last x years with no issues". Will you?

BigSvensk

My "new" 2018 had a full tank when I bought it...wonder what octane they put in? FWIW, got 18.5 mpg on that first tank. Starting my second tank with 93 octane (the station didn't have 91) now.

bbqsoup

I did a full 3 tanks of 87 to test a couple years ago. Same commute, same time, same gas station, Costco 91 and 87, and did it in 3 consecutive weeks - I usually run 1 tank per week.
My conclusion, it felt a tiny bit sluggish at full acceleration at freeway merging and lost maybe .5mpg over 91.

I won't hesitate to use 87 if I need to.

BigSvensk

The 93 I just bought was a 60 cents more than 87 (+21%), and 30 cents more than 89. That's gonna add up over time. I did just find a popular chain of stations locally that has 91 for 50 cents above 87, which is a little better (+18%).

Acrad

I've always run premium in mine but have wondered if foreign market HP/TQ ratings are based on regular unleaded.

United States, Canada, Bolivia, Costa Rica, Dominican Republic, Panama, Philippines - 301 hp @ 5500 rpm & 329 ft-lbs. @ 3500 rpm

GCC, Russia, Ukraine, Azerbaijan, Kazakhstan, Vietnam 292 hp @ 5500 rpm & 323 ft-lbs @ 3500 rpm in Eurasian markets

I've never seen this number in brochures but Wikipedia says the latter are --->. 288 hp (215 kW) @ 5500 rpm 438 Nm (323 lb-ft) @ 3500 rpm

BigSvensk

Just watched a very interesting new episode of Engine Masters on Motor Trend... they did a fuel comparison on a naturally aspirated LS3 on a dyno with 87 (E10), 91 (E10), 110, and 116 octane. They played with timing and fuel/air ratios for peak performance, and in the end... they all made the same power and the engine preferred the same ignition timing. They concluded that unless it is knocking, octane doesn't matter.

The test did not address consumption (mpg).

ASE

^ The final word ... ALL gasoline has the same energy value, so unless detonation is present ... there is no advantage to higher octane. As stated many times in earlier posts, modern engine management will adjust engine timing and the air-fuel ratio to eliminate detonation if and when it occurs (which will slightly reduce engine output) ... but this typically will not occur unless the engine is under hard acceleration / heavy load conditions. So for everyday driving ... go 87 octane. For hard acceleration / heavy load conditions ... go 92 octane. Or just always go 89 octane and have a good day.

NeilB86

Instead of starting a new thread, I figured this is the best place...... I just purchased a 2015 GX in Houston and I live in Minnesota. I decided to run a little experiment and share my results.

Houston to southern Minnesota...total trip = 1,179 miles

Entirely freeway driven. Speeds 65-75 MPH. Averaged 2 stops per tank (including refuel)

4.3 Gallons remaining from 91 octane, prior to 1st fill up ( left in the tank before trip )

1st fill up = Shell

Fuel used : 18.70 gallons of - 91 octane | Distance driven - 384.6 miles | 5.71 gallons remaining | Computer - 21.5 MPG | Actual observed - 22.2 MPG | Estimated full tank distance - 510.6 Miles

2nd fill up = Shell

Fuel used : 17.29 gallons of - 89 octane | Distance driven - 361 miles | 4.96 gallons remaining | Computer - 21.1 MPG | Actual observed - 20 MPG | Estimated full tank distance - 460 Miles

3rd fill up = Phillips 66

Fuel used : 18.04 gallons of - 91 octane | Distance driven - 364 miles | 3.74 gallons remaining | Computer - 18.9 MPG | Actual observed - 18.89 MPG | Estimated full tank distance - 434.47 Miles


As you can tell Shell out performed Phillips but "to be fair" it was contaminated with 89 octane.

Obviously take it all for face value.

ASE

Assuming driving conditions were exactly the same... one word ... Ethanol. More specifically ... "up to 10% Ethanol".

LexusSoCal

i ordered a new 22 GX 460 and was curious about fuel type. I have heard lots of people say that they put regular 87 gasoline in their cars and no issues. I have also heard the complete opposite and people only put 91/93. So what is the consensus here? What fuel do you all use for your GX.

ashschwin

I personally follow the manufacturer recommended octane fuel rating. If the engineers that designed the car call for premium unleaded (91/93 octane), that is what I use on the vehicle. I am sure others will contradict this statement and state that normal 87 gasoline is fine and 91/93 is unnecessary but that is their decision.

chuckNX

Generally Lexus recommends premium for the higher compression engines.

All of their cars will run on regular and many will report everything is fine. However, from what I have read, using regular in a car when the manufacturer recommends premium will result in damage over a long time period (50-100k miles) which most owners will not realize until the damage is done. How much damage? I have no idea.

xychromo

This is an endless debate, really comes down with what you are comfortable with. Would you buy a car requiring premium knowing that it has only seen 87 octane fuel for the past 100k miles? Your answer to that question should determine what fuel to use.

LexusSoCal

Thanks for the responses. I was just curious. For the past 20 years I have only been driving Benz and BMW and have always put 91/93 in my cars but I have heard people tell me who have owned a Lexus, "Oh i Just put regular in it...its a Toyota at the end of the day." I was just curious what other Lexus owners thought. I have full intentions of putting 91/93 in the car because i intend to hold onto the car for several years and that is something very easy to do to avoid issues down the road. I have mainly been a leaser and this will be my first "purchased" car in a long time. Thanks again for all of the responses.