Fuel Economy

[nuarch]

i recently traveled from Miami, FL to Dallas, Tx
and recorded how much i filled up each time
and the mileage i had at next fill up

the car is a 4 door yaris sedan
trunk and back seat full of my life
and when i say back seat full, i meant from bottom
to almost the top of the windows
2 full size adults
and with a total trip of
1623 miles, i did a little side driving
i fueled 4 times and got an average of 39.6 mpg
there was a stretch through tallahassee, fl to port arthur, tx
that i got 43mpg
overall i was pleased with how well the car performed
and i feel sorry for its rear end, because with all the junk back there
any low dip that i was caught not paying attention to
gave me a nice reminder of how low it was back there

[swng]

Originally Posted by nuarch

i recently traveled from Miami, FL to Dallas, Tx
and recorded how much i filled up each time
and the mileage i had at next fill up

the car is a 4 door yaris sedan
trunk and back seat full of my life
and when i say back seat full, i meant from bottom
to almost the top of the windows
2 full size adults
and with a total trip of
1623 miles, i did a little side driving
i fueled 4 times and got an average of 39.6 mpg
there was a stretch through tallahassee, fl to port arthur, tx
that i got 43mpg
overall i was pleased with how well the car performed
and i feel sorry for its rear end, because with all the junk back there
any low dip that i was caught not paying attention to
gave me a nice reminder of how low it was back there

Nice numbers nuarch!
Just for some discussion, I believe for long trips over smooth road surfaces with few stops, load is often less harmful to fuel economy than other factors. What a heavy load (I mean one within safety limits) can usually do, apart from affecting your handling, is to cost you more fuel to reach the desired speed and more heavy braking to slow down/stop. Yet, the momentum caused by the load can actually help you maintain speed for a longer distance. This also means you can lift your foot from the throttle earlier whenever you want to slow down/stop.
Once you reach the cruising speed, friction of all kinds, including wind resistance, becomes the main factor adversely affecting your fuel economy. I venture to guess that your long trip must have been a smooth one (except the unexpected dips you mentioned) with few stops (relative to city driving), making your mpg numbers so adorable.
I envy you for having had the opportunity to travel such a long distance. I struggle with city traffic every day. Even my so called highway drivings are short and full of needs to slow down or stop.
Still, just like you, I am happy with my Yaris!
Thanks for your thought provoking report above!