Crazy high trip mileage + just-ok city mileage = pretty good average

[Suzandy]

Common sense and work experience leads me not to believe every cool number that pops up on a readout. So the pic is from my dashboard, but the numbers I give below are calculated from my odometer (I gotta believe in something) and a very familiar relationship with local gas stations.

I live on one side of a big mountain and work on the other side of the big mountain. The altitude on the Home side is about 1,500 feet higher than on the Work side. Because of my commute timing, traffic is much lighter when I'm heading to work than when I'm heading home. I am using a 2-lane, 55 mph state highway until I reach city streets, meaning my actual road speed is around 53-62 mph depending on conditions, then ~45 mph with stop-and-go. There is a little village on the way with two traffic lights that are green just as often as they're red.

Gravity is my friend on the way to work. Morning at high altitude is very cool, so no a/c. With few cars creating no stop-and-go, I see 76-89 mpg on this leg depending on wind direction and traffic light color.

Going home the engine is working much harder to climb back up the mountain, way more traffic to contend with, a/c turned on any time the engine isn't under load. 38-44 mpg on this leg.

If I take I-40 instead, a realistic safe speed to run with traffic is anywhere between 70-80 mph in the slow lane. Doable but takes my mpg down to about 60 down the mountain, 37 up. No good.

City driving in Albuquerque is murder on the gas tank. Stop-and-go, bad/no traffic planning, erratic drivers and hard acceleration to keep up with the majority of traffic (we have lots of big powerful pickup trucks - no hate - I have one myself.) I don't seem to do better than 39-42 mpg in town, so while I have impressive highway fuel economy I lose a lot depending on how much I have to drive in town. Therefore, averaging 47-54 mpg on the tank. If it was practical (or fun) to shift at lower engine speeds and maintain a little lower road speed, I'd get better city mileage. However, going slow here is neither courteous nor safe, and if I'm driving around a lot in town, I have a lot that needs to get done. Also, it's hot here, so the a/c is on a lot. We'll see what happens when the weather cools off.

My longest highway trip yet was from Edgewood, NM to Durango, CO and back again. There are some steep hill climbs that I wound up taking slower than I liked with engine speed holding around 4200 to make it to the top, plus a nasty wind storm on NM550 that had people pulling off the road altogether. Trip average was 62 mpg.