[slowmover]

I did this seven or eight years back: to more closely approximate Hwy mpg while in the city. The average speed is better (average, not absolute), the difficulty is in avoiding stops.

One has to be rigorous about the fewest engine starts. Constant use of engine block heater. And route planning.

The key was that, 90% of us go to 90% of the same places 90% of the time. Besides work, the usual round of errands.

I had a couple of routes to accomplish it all. Both involved using a freeway to go to the farthest point first. Then, no left turns, park for easy egress, etc. Used a four-piece grille block to force coolant temps.

And, as discipline, no driving at all at least one weekend day.

20% improvement from previous. I use 24-mpg for highway (in a pickup loaded 1100-lbs over baseline). City, in this period was 22 versus 18.

I've detailed this at greater length elsewhere. And on RV plus truck forums that to do as much would have paid for 5000-miles of vacation towing of my travel trailer based on a solid average; and at the then current fuel price

No one has ever taken me up by interest. This was always posted to specific threads on fuel economy. Including this forum around RV topics.

There was no sacrifice in convenience. I never did walk, bicycle or do other substitutions. No public transport. Nor shift a trip to my wife and her car.

As always, it's the percentage gain over the baseline.

Took it as a challenge from Diesel Dave as he set his record-breaking distance from one tank of fuel
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