Speed Limits and MPG Rant

2013 Ford Focus ST - 23 city / 32 highway / 26 combined

This is my expected mpg (if you don't know off hand what yours is, you can check here). My daily commute is classified as "city" but is really just a few miles of stop signs, streetlights and terrifying Massachusetts drivers. Throw in the highway about 3 times a week and my weekly mileage breakdown between highway and city is about 25% highways, 75% city. I average about 24 mpg combined...lower than expected!

Or is it?

The EPA Estimated MPG figures assume 55% city and 45% highway driving. Driving more city miles with frequent starts and stops is (typically) less efficient so my 24 mpg total makes sense.

But what about when it's purely highway? Can you and I yield the expected highway mpg?

Short answer, yes!

In both my leased Fusion from two years ago and my current ST I have been able to get above the expected highway mpg. That's great! But boring and a little misleading.

Speed Limits and MPG Rant

Highway MPG tests are done at a steady 55 mph. Let me say that again: 55 mph. There are a couple stretches of highway near me that have 55 mph speed limits but most across the state are 65 mph zones and some people have been making (quiet) noise about increasing the speed limits to 70 mph. Factoring in the fact that the majority of Massachusetts drivers believe the speed limit is 75 mph, and the ST doesn't believe in the number 55, leads me to less than advertised highway mpg. To test this I filled up near the highway last night, reset my mpg calculator thingy and drove home purely on the highway. I got home having averaged 33.4 mpg after cruising between 55 mph and 65 mph, never passing.

Doing 55 mph on the highway is fine AS LONG AS YOU GET THE FRICK OUT OF THE LEFT LANE! My thought on doing 55 when everyone is doing 70 (or, in Massachusetts, ~3500) is that the flow of traffic gets disrupted and could, in certain circumstances, cause a crash. I liken it to when someone merges onto the highway at not highway speeds on a two lane wide highway...not always great.

I know this subject has been beat to death over the years as gas costs and environmental concerns have most people thinking about fuel efficiency. I also know that, in the name of fun and spirited (but safe) driving, we may be more willing to sacrifice some dinosaur remains for higher rpms. But if normal conditions are not used as baselines in testing and reporting for anything, how legitimate is the test and report?

Speed Limits and MPG Rant

Not everyone can (or should) be like Texas but when it comes down to it the expectations of speed limits and the capabilities of our vehicles today are a little out of whack.

If there is an update to anything I just said, fill me in. I had the basis of this post in my head since last night and didn't research anything.