Incredible highway mileage 2006 Toyota Corolla

[smurty]

I have a 2006 Toyota Corolla that is (really) well maintained. Has 105K miles on the Odometer and I decided to do a Highway only mpg test to see the theoretical max I can achieve. I limited my max speed to 60 mph, mostly drove on cruise, rarely ever used the brake (anticipatory), used the A/C about 50% of the time, and if I went up a slope, then I coasted down in neutral (only to cancel slope effect), and drove a total of 387 miles before I refilled to full tank to get the exact fuel consumption. I filled only 7.89 gal (fuel spit-back, no excess) that netted me 49 miles/gal !! Is that even possible ?

I am going to do it again to confirm. Any insights into making the test better or more reliable ?

 

[rk97]

It's possible, but your sample size is far to small to be sure.

For reference, the best mileage i have gotten from my 2003 was achieved driving from the East side of Cleveland to Indianapolis, and back again. I was doing more like 75 the whole way, and ran the AC almost the entire time. I got 38 mpg.

slowing down to 60 mph would really increase mileage though. I don't mean to be condescending by pointing this out, but wind drag increases exponentially with speed, so if you were really doing 60 indicated, that would make me believe 40+ mpg easily.

the other thing I would look into is the net elevation change. If you ended up at a lower elevation, you were going down hill more than up.

And then there's the fact that you only did this on one tank. When you re-filled, the pump shut off whenever the sensor decided your tank was full. The odds of that being at the exact same level as when you left are slim.

Sign up for Fuelly (get the app) and start tracking ALL your driving. Then you'll get a better sense of things. Over 11,000 miles (tracked) I average 34 mpg.

 

[smurty]

Thanks for all the tips.
The exercise was just to get best possible Hwy mpg distance mileage, but I see your point.
I drove at 60 exactly for that reason - to reduce drag (as drag force increases with the square of velocity).
Elevation change (good point) but in my case wont be an issue as I am doing back and forth trips.
Sensor shut off - very good point, and noted. Will average over several fills.
I signed up for Fuelly, lets see - thanks again.

 

[rk97]

if nothing else, fuelly gives me something to do at the gas pump. Driving as much as i do for work, it's also helpful to keep track of how much i'm spending on gas, and how much I would have spent if i hadn't replaced my Altima with the Corolla.