masboy

iTrader: (30)

yupe ^^^

https://www.clublexus.com/forums/gx-...r-regular.html

rominl

iTrader: (4)

using lower grade and you might suffer on mpg as well.

personally i would just stick with premium. it's really not much of a difference in price at all, which is only thing that matters overall anyway, if at all

MSGX470

Thanks for the warning, I get a kick out of those kind of people, if you're not interested a topic why waste time reading it at all?

That seems really low, I get no less than 15mpg in the city, although I do not have a heavy foot either.

Agreed, I was kind of looking for someone using regular to see if they had any issues, not thinking of switching anytime soon but I do live in the south where hurricanes and tropical storms are common and sometimes premium is hard to come by after those kind of storm events. Guess I could just keep a bottle of octane boost in the back.

JuLeX47

Use the search function, but I'll show you some hands

RickC5

Since our '08 seems to run perfectly on regular, I doubt I will ever try premium. Would it run better on premium, or get better mileage? Don't know & don't care.

LexGX

iTrader: (1)

I have an 04'. I use regular on the regular (no pun intended). But every now and then i'll put premium in it. Hasn't affected me at all.

TopGear300

I have been looking into this briefly.

I almost consider starting a new forum not on quality of gas but the variability of gas stations. There does appear to be a difference from a cheaper station (like Wawa for the east coasters on here) as opposed to a Shell or an ExxonMobile.

Before I did my research I noticed with:

Regular the GX got 17.6MPG average
Premium in the GX I saw a dramatic 0.1 MPG improvement totalling 17.7 MPG AVG

After my research, I learned particularly when these engines get a little age under them, it is essential to run fuel injector cleaner in the tank every so often. Specifically I chose chevron techron concentrate as discussed in another post.
(https://www.clublexus.com/forums/gx-...injectors.html)

Throw this in either Regular or Premium and you will see a more noticable change. The GX says shes doing 18.6 MPG AVG today with just regular in and after a few fuel injector cleaner bottles run through the system. I recommend keeping up with this!!!

CHEERS

rbx10

Thanks TopGear for the reco. I never thought of using Chevron Techron in the GX as I never seen that recommendation. My truck is an 08 and has 70K on the dash. I would need to do some research.

As for gas, I use Premium on an regular basis. The manual does mention that you can use Regular temporarily but you have to go back to premium. I think premium will have a better impact on the GX engine longevity.

I stay away from BP gas, I tried it twice and makes the car feel so heavy and sluggish, I only use Exxon.
Thanks again
-rbx10

SmittysGX

WOW! these old threads bring back the good times. I cant even remember gas that cheap....

fantic

Just curious if everyone uses premium fuel or like me just 87 octane. When gas hit over $ 4.00 a few years ago I started using 87 and never went back. At the time did some milage comparisons and didn't notice any difference. I have pulled a 6000 lb boat and the engine never complained. I'm sure there are some use cases for the premium fuel but not for the driving my wife does.

cssnms

Going on 9 yrs and 90k miles, I never noticed a difference, so I only use 87 and I too pulled a heavy load with regularity. Depending on the year, it's more of an emissions thing to use premium.

tecman

This thread was combined/moved with another one at least once, hope it helps.
https://www.clublexus.com/forums/gx-...s-regular.html

cssnms

That is a 2nd gen GX thread. Different motors 1UR-FE vs 2UZ-FE.

2005 and older 2UZ-FE engines called for 87 or higher octane and 2006+ called for 91 or higher due to newer emmissions requirements/turning (ULEVII, SFTP). My owner's manual calls for 87 octane. All model year engines will run on 87 without issue, but you may notice a slight decrease in performance (output/MPG's). If you have not noticed a difference in gas mileage or performance or engine knocking stick with what you are doing.

RCsGX

It's been talked about many times before about our 2uz-fe engine...there's no reason to use premium.

tftimm

When I bought my 2004 with about 104K, I assumed since it was a Lexus it needed Premium, so for the last 20 months, I have been putting in premium.

Well, for no reason, I'm comparing gas mileage and it says that I should be using Regular. So, should I go to 91 for a few tanks, then 87 or is it OK to go straight to 87, or fill up now when I have 1/2 93 in there, and then switch, or could end up causing problems with timing, etc. since it has been running premium the last 2 years or so? I don't know what the previous owner was running, it was a 1-owner vehicle before I bought it.

At about 120K, the car runs solid, smooth, no oil drips, etc.

Saving $0.30 a gallon, $6 a tank a tank or so. I actually read that 87 octane will give you the best mileage, 93 will give you the best performance...come on, its an SUV, I'm more worried about gas mileage.

Thoughts?