gxman1

RC,

Did you ever figure this out? I have noticed in Summer my gas mileage goes very bad and in winter it is all good. Keep in mind over 100 F in summer.

RCsGX

Hi gxman1!

As of yesterday I got 10.5MPG on a tank, all city driving.

A few weeks back when we were at the beach for a week I got 15.8MPG, also all city driving, so I think my MPG is bad because it's a constant stop and go where I live. At the beach there was only a few lights and the rest is a road (SR789 45MPH) following the coastline so no stop and go, just straight cruisin.

We're going back for another week at the end of July. At least during those beach weeks I get GREAT gas mileage for city driving.

MidniteGX

My 04 shows the live gas consumption readout is through the roof when the engine is at Idle. Yet when you're moving at even a very very slow rate of speed it shows a very very low rate of gas consumption. I think this may account for the higher gas mileage ratings on stop and go traffic and I also think that this might be a bug. I've noticed on the latest Lexus readouts when you're idling the readout for the live gas consumption shows at extremely low so they've obviously corrected this. has anybody seen a correction done in this on the later models of the GX?

chiph9

The in-car readout on mine (2004) is about 2 mpg too optimistic.

I use fuelly.com which uses info I enter at each fill-up.

Chip H.

470reasons

On one leg of a recent trip, I checked the mileage over a 2450 mile stretch, I averaged 16.55 miles per gallon. My odometer reads 10% low due to the larger tires. At first I thought my mileage was really bad. Compensating for the odometer error, mileage is darn good. Between Laramie and Rock Springs WY the mileage dipped to 13.8.(mountains). Just re-verified the odometer error is exactly 10% this morning. From my driveway to a particular business was always exactly 100 miles. With the new tires, this morning, it was 90 miles showing on the trip meter.

Mileage is the actual calculated figures. NOT THE TRIP COMPUTER B.S.!

RCsGX

What live readout are you referring to?

The only live readout I see on the trip computer is the MPG readout which adjusts according to RPM / speed and at idle it shows 0MPG.


When hand calculating my MPGs, my trip computer has always been 1MPG optimistic.

gxman1

I can see this for sure, in summer hot months my mileage are terrible. Keep in mind when the temp is around under 85, great mileage. when it is over around 90 F I get terrible mileage, I would say consumption deteriorates by around 20%-25%. I have driven on Highway and it is terrible.

RCsGX

I get better gas mileage in the winter months even though most say you'll get worse due to the cold and due to "winter gas".

MidniteGX

I agree with your opinion of the computer's accuracy. I only use it as an occasional guide but never rely in it for hard facts.

Being in Canada it's set to kilometers. The "live" readout is litres of fuel per 100 kilometers in real-time display. This is what I can select to display among all the other settings like range, altimeter, air temperature and the trip computer's "calculated" mileage.
I'm hearing from you that your real-time display shows 0 mpg at idle. Correct?
Mine shows 99litres/100kms which a litre is basically a quart of gas and a 100 kms is about 63 miles.
The point is: it should show 0 at idle.

470SNC

pretty sure the poor mileage is due to heavy 285s plus the lift, my FJ mileage went down considerably after lift/tires

RCsGX

Nope. I started this thread when I first bought my GX back in '12 and it was stock ride height and had the stock wheels and tires. Oddly enough I didn't take a MPG hit with the lift and larger tires. I only added 4.6lbs. per corner with the larger 18" setup so it's not that substantial but I'm surprised the lift didn't hurt.

Based on other lifted GX's I'm around the norm with lifting / larger wheels and tires but I shouldn't have had that crappy MPG when at stock.