LOL.. I have always done the same with all of my cars.

 

Just took a trip to Laughlin a couple of weeks ago from Phoenix and got 25.5MPG.......but usually around town about 18-19.

 

I recently ran highway 335.2 miles at 80-90 mph with 10-20 miles stop-n-go up to 40-50 mph around town. My low fuel light came on, I went to fuel up and I filled her up at 16.4 gallons. So 335.2 divide by 16.4 = 20.439 mpg. At my present average with 3.4 reserve in the tank - I could have gotten over 400 miles per tank. Thats great considering I have TC and LSD and K&N Drop in filter.

When I was completely stock - I was getting 25-26mpg on the highway..
Considering stock EPA estimates 23-24 mpg on a stock GS400 but that seems to be a overestimate if you understand the way how the EPA's test criteria.

Then again, Lexus cars are extremely efficient.
I'm more than statisfy with my gas mileage even after modding.

 

I also get 25 to 26 mpg on the highway in a stock GS400. I removed my K&N filter and replaced it with the stock paper filter and Torquemaster plugs and my mileage went up from 24 to 26 per gallon highway. The throttle body stays cleaner with the dry paper filter, as the oil was leaving the K&N and lodging in the intake. My oil seems to stay cleaner longer too.

I see that I am not the only one that has a low fuel light that comes on too soon. I still had 3.5 gallons left in the tank, and the needle was on "E". No way to fix that though, so I know there is more gas in the tank than the needle says. That is my safety reserve, just in case.

 

I get about 18-19 on 80% stop and go highway types (55 mph with traffic lights) and up to 26 on long open freeways. 98 GS400 stock, 5 out of 10 on the aggression scale.

 

i get around 18-20 mpg, i have ecu, intake, exhaust, 19's so i guess it's not bad, i don't try to drive it hard though, just cruise around

 

on my gs4 in NYC i get about 11-15 mpg

 

Iam doing aboyt 40 miles on the highway each way to work and iam average about 22 -25mpg on the freeway. On a full tank of gas i will put on close to 400 miles on till its empty. I have no engine mods other than a k&n filter.

 

in the city and daily driving, I get around 20mpg....when on go on highway trips...I average around 25mpg if I set it on cruise around 75mph...however, when I had put on the 3.76 Supra TT gears, it had reduced my highway consumption to around 18-20mpg....which was unacceptable at the time since I was planning on alot of road trips.