When should you use cruise control, and does it improve gas mileage?

Originally published on Oct. 11, 2022

MINNEAPOLIS - Some drivers love it while others don't trust it. The debate has played out in several cars, often between couples.

Christine asked us: When should you use cruise control? Good Question. Jeff Wagner hit the road to find answers.

Whether it's for the simplicity of not having to hit the gas pedal, or the necessity of making sure you're not speeding, a few finger taps on the steering wheel is all it takes to give your foot a break.

"I trust it under the right condition," said Bob Larkin, director of automotive service technology at Dunwoody College of Technology.

So what was cruise control designed for? 

"The basis is really to help with driver foot fatigue on a long trip," he said. 

That means using cruise control specifically for interstates and highways.

"Minimal traffic, minimal distractions, road's pretty level. That's probably the thing that it's really most designed for," Larkin said.

It's also an opportunity to improve gas mileage. Natural Resources Canada did a study in which a car was set to about 50 mph on cruise control. It consumed 20% less gas than a car cycling between 46-52 mph every 20 seconds.

When should you not use it? The answer to this question is much longer than when you should use cruise control. Larkin advises against using it on city streets. 

"Taking the time to set that cruise control, then have to disengage that between city blocks can sometimes become a hindrance," he said, adding that there's also more distractions in a city such as bicyclists, pedestrians and stoplights.

Drivers should also avoid using cruise control on hilly terrain and when they're tired, two situations that require more active participation from the driver.

Lori emailed us because her husband said avoiding using cruise control while it's raining is outdated info, a debate she was determined to win.

Larkin said slick conditions, such as rain, snow, and ice are dangerous for a driver with cruise control engaged. The tires can start to spin, leading to a loss of control.

"If the driver's actually in control, you'll have a little more feel, a little more sense of what's happening and can actually react quicker," Larkin said.

Newer cars have adaptive cruise control. It can slow your car down if it senses the car in front of you slowing down, then speed up again when it's safe to do so.