[slowmover]

Needs a baseline:

Top off fuel at an Interstate fuel station near home. Early on a weekend morning.

Fill slow to first automatic cutoff. Ease onto Interstate ramp and engage cruise control just below 60-mph before entering main lane. Travel 100-miles outbound, and using a pre-planned exit and crossover with no stops, return to that pump in the same way.

Refill at same pump in same way.

This test can be replicated by anyone. At any time. Only temperature and traffic volume differ.

Remember: cruise control ONLY. This IS NOT about highest possible MPG number. It’s the baseline for all other comparisons.

As you make this drive note instant mpg. In the future, any changes will show themselves here. There’ll be a high on this device, and you’ll have the trip Average. These are for comparison purposes.

As example, I “know” my pickup can be loaded to just over 1,000-lbs above TARE, and, at 59-mph/1,725-rpm I won’t EVER fall below 24-mpg despite weather, traffic volume or other extraneous condition. Over my initial period of familiarity (the first 10k Miles for anyone), I adjusted myself to what the truck wanted. So that 24-mpg is dependent. It’s my adjusted baseline for the South Central United States.

An empty vehicle save driver isn’t a test. The test comes with a load. As against the empty baseline, how does it fare?

A plan has these elements. Be inclusive. Downhill mpg in an empty car is meaningless by itself.

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