Does Cruise Control Save Fuel or Use More Fuel?

the only way to find out. would be to do the same trip twice. one with and one without.

but i'm like you. in the w9 i think it used more. and i think it had something to do with the fact that throttle seemed to be greater with the cruise. in other words, if i had to slow down for whatever reason. i'd kick in the resume. and there was better throttle then using the pedal.

but that's probably another question that depends on the truck. kind of like that physics and fuel argument awhile back. not every truck holds true to physics. i've driven 3 and only ONE holds up with physics.

but as for the cruise. my switch went out once. and i hope i never have to use the foot again.

 

Correct. I meant to take the word 'true' out before I posted and change it to 'more accurate' but I forgot to do it before I hit submit. It wouldn't be a true answer. But I don't think the true answer i.e. as it applies to all drivers and all trucks is as important to the OP as a reasonably accurate but still anecdotal answer which applies to that one specific truck/driver combination and my suggestion would accomplish just that quite nicely.

 

Most drivers can never get better fuel mileage that the computer in cruise. Not that we are dumb, it's just that the computer is set in cruise to minimize fuel usage.
Jack

 

The foot/brain over reacts many times. Building momentum takes fuel but cruise will let off the throttle and even throw the jake on if you are rollercoasting. What I do is use the cruise but over ride the throttle on the down/up part or turn the cruise off all together in the hills. Engines like an ISX come alive at 1200 and will climb more efficiently than at say 1600. Overall, cruise is more efficient.

 

Cruise does help to make a truck more efficient, as a owner op I use my cruise religiously. But the main factor to any fuel savings is mainly speed. 70mph=5.5 to 6 mpg.
65 mph =6 to 6.2mpg 60 mph will get you to 6.5 to 7 mpg or better and 55-60mph will keep you up to 7.5 or even 8mpg on average, secondary factors that help out are cruise control used regulary, low rolling resistance tires with proper inflation, aerodynamics and weight of the truck and load weight, as well as road conditions, weather, wind direction and the type of trailer you pull and how much drag it creates. But in general to answer your question FROM MY EXPERIENCE it absolutley helps to save fuel when you consistently use the cruise.

 

In my truck and places I go I lose fuel mileage on cruise. Unless I am emty. the reason i think is as I see a rise in the road I start giving it fuel as I top at I back off. The cruise has a delay on both counts.

 

Actually, it is the cruise control that is dumb, as it only programed to hold a certain speed, no matter the terrain. It cannot anticipate a grade, nor the steepness of that grade.

 

That's why there is a cruise cancel on the clutch and a resume. A floater will turn the cruise off in the hills. Other than big hills, speed and rpm's go hand in hand.

That driver that is up and down on the throttle burns more fuel than the easy pedal driver. You can listen to some of them sometimes, you'd think they are playing the bass drum the way their foot moves.

 

I have driven trucks with cruise, my Suburban has cruise, my Corvette has cruise, my big truck does not have cruise and never has had cruise. That wasn't even an option, in 1984 when it was built.

 

Why ask mathmatical problems of truck drivers? 5/4 can't do fractions and 50% are below average.