sprocket

For some reason the search function won't work while on my laptop so I decided to start a new thread for this.

I've decided to keep my 2004GX for a while since it has good tires and I had the 90k service done back in February. Since I'm now driving it daily (was driving my wife's Prius for a while), I decided to hand calculate the mileage on the last 3 or 4 tanks. Using typical 87 octane E10. GX has 96k on it.

100% in town has ranged from 11.8 - 13.2mpg.

95% highway at 75-80mph 16.8mpg.

Are you guys in the same ballpark?

DirtyGX

I get 18-20 on the highway depending on how I drive and how much passing I do. Try bumping up your octane rating and (if you can) ditching the E10. I find that almost all of my cars the extra power provided by the higher octane nicely offsets the cost of the gasoline. It doesn't always pay for itself in MPG, but the power offsets are nice.

The best we can get in Utah at chain gas stations is 91 octane, and it's what I use in everything now. The BMW specifically asks for it. The Escalade simply drives better with it, and the GX seems to get a bit better mileage as well as better driveability.

Try a tank, and see what you think.

PS, Toyota has never really given a damn about gas mileage, I've owned 6 or 7 toyotas, and they all got worse mileage than the same type of vehicles in their class. However, they last 4x longer than those other vehicles.

PPS, you want really bad gas mileage? Buy a landcruiser or the LX equivalent.

chiph9

Currently averaging 12.5 mpg in town.

http://www.fuelly.com/car/lexus/gx470/2004/chiph/266955

However, there are a couple of 10% grades on the way to/from work, and I run the A/C from March to November.

Chip H.

OG Dada

iTrader: (10)

I'm constantly getting 13mpg city driving and 19mpg highway. I use 91 Premium all the time too, that's what's recommended right? When the previous owner handed it over to me, he had it full tank with regular unleaded and there was no power at all. The engine was reacting so badly it wouldn't idle steadily. Couldn't complain though 'cause I used to get 15mpg city driving in my old SC400.

YoshiMan

Yeah, that's about my mileage too. 13-14 in town, 16ish on the freeway.

Its certainly better than my old 89' Landcruiser, which couldn't barely pull it's own weight and got 9-10 MPG. and much better than the 6-8 my old landyacht Cadillac gets!

sprocket

At least it seems I'm in the same ballpark as many. I've always used 87 regular unleaded with no problems. Getting 49mpg in the Prius was nice, but it didn't make sense to insure 2 vehicles.

470SNC

Try cleaning your MAF sensor, I get 15.2 average pretty steady driving half freeway/half local for my commute to work daily. Also I only run 91 octane

Johnny Rad

I'm with Yoshi and the OP.
Fuel efficient the GX ain't.

UpStarr

Premium Unleaded FUEL ONLY see owner's manual
Your gas mileage is crappy because you use crappy gas! The title of this thread should be "Crappy Gas Results"

lesz

Without question, the two factors that are going to have the largest effect on mpg are where you drive and how you drive.

I've had my 2005 GX since it was new. My mpg is consistently in a range of a little over 20 mpg, which is actually calculated and not what the vehicle's computer says. But very little of my driving is done in stop-and-go conditions, and my driving style is rather conservative. If I drive more aggressively, my fuel economy can drop by 3-4 mpg. Also, during the winter, I expect a drop in fuel economy as the typical temperatures drop.

During almost 10 years of owning the GX, I have only used regular 87 octane fuel. There have been several threads over the years about fuel grades and the GX. Most have concluded that the only reason why the "recommended" fuel grade for earlier GX vehicles was for premium grade fuel was that, by making that recommendation, it allowed Lexus to qualify the GX by EPA requirements as a higher emissions level vehicle. The GX has a compression ratio of 10:1, and vehicles with 10:1 (or lower) have absolutely no need for premium fuel, and using premium fuel in them results in no benefit with regard to mpg. While the wording in the GX manuals changed over the years, the general thrust of the wording has been that, while they are recommending premium fuel, using 87 octane regular is fine.

Further, with multiple Lexus/Toyota engines, including the 4.7 liter V8 and the 3.5 liter V6, originally, premium fuel was recommended, but, after a few years, Lexus/Toyota changed the recommendations for those same engines to 87 octane regular, and those changes in recommended fuel coincided with changes in the EPA requirements to qualify for a higher emissions rating. If the use of regular fuel eventually for those engines was fine, there is absolutely no reason why it wouldn't be fine in the earlier years when those same engines were used.

If you do a forum search, you should find other threads where fuel grades are discussed, and they generally end up with a consensus view that is consistent with what I explained above.

sprocket

This is from the 2004 Owner's Manual:

Octane rating
Select Octane Rating 87 (Research Octane Number 91) or
higher. For improved vehicle performance, the use of
premium unleaded gasoline with an Octane Rating of 91
(Research Octane Number 96) or higher is recommended.

470SNC

All in all, the GX does not require 91. Will it get better gas mileage with 91, yes. YMMV

OG Dada

iTrader: (10)

That's funny, here's what it says on mine;



Mine's a 2008. I guess it's different in the older models... But that's weird though, 'cause my 96 SC300 also requires premium, it even have a reminder on the gauge cluster. Toyota also require the higher end Camry's, the V6 ones, premium gas too. I'm pretty sure Toyota/Lexus require premium for their higher end cars.

UpStarr

please refer to post #9,11 & 13

GXallday

2005+ have the VVTi engine and that's when the 91 octane was a "requirement". 03-04 run on regular 87.

That is not true. My Camry with 2GR-FE 3.5L V6 does not require 91 octane.