hypermiling
Tony, a hypermiler, tracks his mpg for every tank.
You're not truly driving efficiently until you're a hypermiler.
Some hypermilers remove side-view mirrors to reduce drag, and some even shut off their engines while coasting.

SMART Vocabulary: related words and phrases

On the road: driving & operating road vehicles
aquaplaning
back someone up
biting point
boxed in
branch off
chauffeur
gun
handle
lock
pull
pull someone up
push start
range anxiety
reverse
road rage
run away with someone
skid
speeding
steer
ton

You can also find related words, phrases, and synonyms in the topics:

Environmental issues