[slowmover]

Highway travel is about steady-state cruise.

As the iron rule is vehicle spacing (hundreds of feet; NEVER any traffic next to one) finding a cruise control set speed is ALWAYS just below most other traffic.

1). No lane changes
2). No acceleration or deceleration past entry & exit, per se
3). Constant use of cruise control is the predictor.

Managing overtaking traffic is the only challenge. Some new habits.

The “sorta economical high speed” will be 64-66/mph dependent on traffic.

The Wall is 60-mph. 59 is the true high mpg speed.

The best compromise is 62-mph. Other traffic will have a safe overtaking margin of speed (that you don’t have to cancel cruise to get them around you faster and avoid traffic building up), as it’s close enough to average to not be an outlier.

The operator is always more of a problem than the vehicle. (At 50-mph I can be above 30-mpg in my four ton pickup).

4). Planned stops (in same direction of travel)
5). Time of day (to avoid the worst traffic)
6). The right blend of factors to avoid steering changes, speed changes and to use cruise control every moment.

At 75-mph how often did you change lanes? How many times did you have to use brakes? How many times did you come within 300’ of the vehicle ahead of you?

These are the marks of the unskilled and high risk driver. MPG is a marker of operator skill, which is first safety.

The irony is that THE AVERAGE SPEED difference between 62 and 75 WON’T be 13-mph. Maybe 7 or 8 given traffic volume. And on a trip of under 300-miles, that’s an irrelevance. (It’s not ever justified).

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