Unexpectedly good highway MPG

[Thymeclock]

I just returned from a 600 mile round trip in the A/T '09 hatchback. Our car is used only in local city driving, and it gets only 23 MPG locally.

With the A/C on for the entire trip, the scan gauge was reading 37 MPG at 70-72 MPH. If we drove at 60-65 MPH we got 39.5 MPG. I could hardly believe it! Manual calculation of actual fuel used confirmed this. That's considerably more than the EPA estimates for that year, which as I recall were only 35 MPG highway.

The only thing I can attribute this to is having the (original) tires over-inflated to 40 PSI. The car was very comfortable for two people to travel in, and I enjoyed driving it.

Now if there were only some way to reprogram the TC lockup on the automatic transmission and improve the lousy city MPG...

[arokace]

wow, that is exciting to hear. I need to get meh tires inflated some.

[freddingo]

That is pretty amazing. I do about 90% city driving and managed 26mpg on my last tank, I may need to find an excuse to go on a highway trip.

[petrified.rabbit]

I got 400 iles out of a tank two winters ago when snow caused me to drive my 60 mile each way commute at a steady 55 mph..

That was with @5 minutes city driving on each end, but still, slowing down really improved the mpg.. even though I have a manual.

[Thymeclock]

I got 400 iles out of a tank two winters ago when snow caused me to drive my 60 mile each way commute at a steady 55 mph.. That was with @5 minutes city driving on each end, but still, slowing down really improved the mpg.. even though I have a manual.

In my case speeding up improved the MPG. The sweet spot is between 55 and 70 MPH. This is a bipolar car: it gets incredibly good MPG at highway speeds, but abysmal MPG at anything under 45 MPH. It's great for those who live in very rural places. But if you live anywhere near a city where the speed limit is below 40, you're screwed.

[Lefty]

My 2008 Aveo5 with 113,000km on the odometer has just recently started getting 37-38mpg on the highway at 70-75mph!!!
But in the city the best I can do is 25-26mpg. I calculate this using an ap on my Blackberry every time I fill up for the last 2yrs.

Prior to this month, I could only get 32mpg on the highway. I don,t know what to say, I haven't changed anything.

[Overdrive]

I've usually get about 31-32 in my day-to-day driving which is mostly city with some highway. But when I go on a road trip of an hour or more, it jumps up to around 36-37 mpg going about 70-75 mph. I have a 2008 Aveo LS manual.