On flat straight roads there is only “marginal” difference but on hilly and curvy roads the difference can be major. I have owned a 1985 Crown Vic, a 1991 Crown Vic, a 1996 Crown Vic Police Interceptor and currently have the Mercury Grand Marquis 2004 model which is of course the same car. The best mileage I ever got with cruise control was 28 mpg traveling southbound on I-95 which was not hilly, it was close to flat. The best I ever got WITHOUT cruise control was 31.4 mpg with the Mercury driving in very hilly country, some of it almost mountainous. I call that more than a marginal difference. Simply put cruise control is NOT a gas saver in reality. If you prefer to use it fine, you will get no argument from me, I just want people to stop kidding themselves that using cruise control gives maximum mpg.
All I was trying to put forth was my personal experience.
Your personal anecdotes are no more and no less accurate than mine. That you choose to denigrate the usefulness and accuracy of Cruise Control is not *MY* issue.
Why you want to decry ANY tool that can be a boon to those who travel long distances is most worrying, since I am shocked that you consider it your business to denigrate the usefulness of the tool.
How strange that a poster here would try to decide for others what is best, this being a conservative (leave me to my own devices) website. Nor should any worries about CC’s use by others be your concern or business!
I have driven literally millions of miles in my personal vehicles, let alone the time I have spent driving for my employers.
Cruise control is one of the most useful and time-saving tools there is for those who drive long trips regularly. You avoid tickets by staying under the speed limit, you save time by not slowing down when not necessary, and you are far less tired at the end of your 10 hour drive.
Yes some of this comes at the MINOR expense of a few ounces of fuel every dozen miles, but so what? If an additional 10 cents per mile is going to destroy your budget, you are WAY over your head at the beginning of your trip anyway!
Really, fuel savings is a very MINOR consideration when engaging cruise. That YOU bought into the fuel savings thing isn’t MY fault. I LIKE getting 30+ MPG while not getting a tired calf muscle after driving all day.
You go ahead and cramp up after 6 hours on the road, because you want to save 1 ounce of fuel every 19 miles because your foot is in constant motion. I’ll wave at you as I cruise by your rest stop at 75 MPH still comfortable and enjoying my drive while you walk off your cramping calf muscles.