Acrad

I also use Costco Premium most of the time and get similar mixed general mileage as hzhao. I can get up to 21MPG in all hwy driving. Not that it matters...most of our oil in western WA state is crude from Alaska refined here in-state.

psun786

Gas quality deteriorate after sitting in the gas station for too long. Different additive and RVP also make a difference, but definitely not 5 mpg difference. Costco's probably has the fastest turn around at pump so that helps the deterioration . But they buy their gas from all over the place (who ever has cheapest batch at the time of purchase)...

I have a highly modified Subaru STI with an aggressive custom tune. It display micro knocking and is very sensitive on gas. From my experience, a busy Shell station usually has the best or most consistent quality. I would prefer Costco over a top tier gas station that doesn't have much traffic. Chevron has decent stuff according to the community, but my car just doesn't like them.

Gxxr

My $.02......

When you get a long weekend soon.... and a hankering to travel and help your car all in the same trip.... You need to clean your fuel injectors and even more likely, actually seat the rings and get that wonderful engine broken in. Your car is suffering from "townie" syndrome. It has likely never been driven at 70mph before you got it, and it has likely never been ran for more than 10 minutes at a time with short trips before you owned it.

Go hook up to a nice, moderate to heavy travel trailer, around 3,000-4,000lbs or so.... make sure you have a fresh oil and filter change and a new engine air filter and a fresh tank of Premium fuel of high quality. Pour some B-12 Chemtool fuel system cleaner in the tank, heck, use a couple of bottles if you want. Bring some more for the road.

Head from Texas to somewhere with Elevation, like New Mexico or Colorado. Getting into the mountains and putting that engine under a constant load will do more than you could ever imagine. Within a few tanks of fuel and some driving in 3rd and 4th gear by manually selecting the gear, you will likely be able to transform your car into what it always should have been.



Even here in Colorado, at 6,000 ft elevation, and the engine being down on power by 20% vs sea-level power, we still get 16-16.5 mpg average around town and 20mpg on the highway in our 2012 GX460

Yurka

Thats quite low, GX is my daily, im from NYC and the last 2 months due to never ending highway construction i was forced to take local streets, meaning red lights and stop signs on every block and its annoying, my MPG is about 13.5-14.5 city, however when i was driving via highway prior to construction which came to about 70% highway, 30% local roads my MPG would jump to about 16.5, i only fill up at BP, ultimate

ejmustang

I recently got an 2016 gx 460 with 27000 miles on it, the computer shows I m only getting 12.9 mpg, is this normal? what could be wrong or how to fix it

bbqsoup

ejmustang

will try tomorrow, thanks

S2k4

I did mostly highway miles on mine when she was still alive... and consistently got 20-21 mpg.

ejmustang

bbqsoup

Zahid

I never trusted the on-board chip to give me a good estimate. The best way to measure mileage is to fill up the tank, reset trip meter and look at the miles driven during the next fill. A simple calculation will give the absolute MPG value that one one can deny.

Nickk6

The calculations are nearly spot on. Its always been within +/- 1mpg of actual reading from my experience.

bbqsoup

chimes

How are y’all tracking gas mileage in your GXs? I see people posting about getting 15.7, 16.5 etc- are you using the old fashioned method of tracking odo and measuring at fill ups or is there an onboard app? My other vehicle tracks it real-time in the info display but I can’t seem to find it on my ‘15 Premium.

Airpirate

Did old fashion method and compared that to the digital read out (avg since fill up). On my 2013 the digital results were exactly the same as manual measurement.