On flat or constant grades, the cruise works best for MPG. hover on constantly changing grades the cruise is regularly changing throttle position to maintain a constant speed. In other words it is accelerating and coasting regularly.... you may notice the automatic transmission will up and down shift depending on the vehicle. depending on how advanced the cruise setup is it may increase gradually or more commonly go to an all or none setting to resume speed. like putting your foot to the floor.. It is doing the all or none If you have used the resume button after braking from cruise say to slow down by 10 mph and the car downshifts and takes off like its floored to get back to cruising speed... You do better by gradually accelerating back to your cruising speed then pressing resume... Non electronic cruises that are cable controlled will surge and often exceed the cruise speed then settle back to the preset speed. This is caused by a streched and out of adjustment cruise cable.. most are easily adjusted and will result in a smoother cruise with less surging
by soutthpaw on February 01 2009
this tip works for 84% of voting Fuelly members.