Living With Your Adaptive Cruise Control

(I'm going to post an article in pieces. So be patient, make comments, and the rest will be added to this thread later.)

Many drivers prefer to manage the speed and following distance in their truck on their own. These people are missing out on quite a few systems that will make their life easier and safer. I will cover the basics of adaptive cruise control and even add in a few tricks that will help you last out the 11 hours you get to drive around the country each day.

This article is based on a Freightliner system, your adaptive cruise control may work differently.

Part One: The Basics

Doing what it's supposed to do, a Cruse Control system will attempt maintain a speed you set it at, including up and down hills. You get to your cruising speed, push the SET button, and relax your right foot off the accelerator. Tap the brakes (or press CANCEL) and the cruise control kicks off. Get back with the RESUME button.

You can also adjust your set speed with the accelerate and coast buttons. The adaptive cruise control will do its best to get you to 3.5 seconds behind the vehicle ahead of you. Hint: if you need to back off from the vehicle in front of you, first adjust your cruise control to match the speed, then hit CANCEL to back off. When you get to the best distance, press RESUME. If you first press the COAST key to back off then hit SET, you'll stay going the same slower speed unless you accelerate. This is a clumsier process.

Stopping Distance

You may have a distance readout showing you how many feet or seconds you are away from the vehicle in front of you. Your company may also get reports from your truck when you tailgate too closely. Not good, and nothing you can do about it without damaging the system. (And that's worse for you!)

If you make sure the on-dash readout shows seconds, you can monitor the seconds between you and the car in front. If it gets less than the minimum time (1 second at Swift), you should back off, (Note: your readout may show feet instead of seconds. There's a Setting you can change to switch to time.)

This distance readout only works when the adaptive cruise control is operating. If you are not using the cruise control, as in local traffic, you won't see the following distance.

The 2018 freightliner I trained on, was able to show you distance and seconds, with or without the cruise engaged. It really helped me see what 8 to 12 seconds really looks like. I am terrible at picking the point in the road, and counting. I loved that feature. My current truck is the way you described.

The 2018 freightliner I trained on, was able to show you distance and seconds, with or without the cruise engaged. It really helped me see what 8 to 12 seconds really looks like. I am terrible at picking the point in the road, and counting. I loved that feature. My current truck is the way you described.

That may be the cut-over year. I drive a 2017, you get either time or distance, not both at once. The deal about "seeing 8 to 12 seconds" is important. If you don't see the real measurement, it's awfully hard to estimate. I learned the same thing.

On the Kenworth t680 that my trainer has, the seconds show regardless of cruise control being active unless something has gotten lodged on the radar sensor. I believe they call it the collision mitigation system.

Errol, I assume you have a Meritor Wabco CMS? I didn't know you could change the feet to seconds! Gonna have to take a look at that. Cruising at 63, my ACC likes to keep me at about 330ft following distance and yells at me when I get within 180ft or so (not exactly sure because before that I'm finding a hole to pass or slowing down).

If I need to back off because I can't immediately pass, I just hit the cancel button and turn on my light/medium jakes depending on terrain and weight. It's nice that the automated freightliners have the Jakes on the shifter stalk; extremely user friendly!

I have whatever comes on a Freightliner. If that's what you have, look on the rocker switches for one that has that "L" arrow/return and the words "MENU BACK". Use the + & - buttons on the steering wheel to move the readout panel to the page that says "Press L to enter the Parked Menu". You can fake it from there.

The ACC will use Jakes better than you can to slow down as needed. My suggestion is to first match speed while you're closer, then CANCEL the ACC, and coast back to at least 1 second, 3.5 is official, then tap RESUME.

Unholychaos says

If I need to back off because I can't immediately pass, I just hit the cancel button and turn on my light/medium jakes depending on terrain and weight. It's nice that the automated freightliners have the Jakes on the shifter stalk; extremely user friendly!

Errol replied:

My suggestion is to first match speed while you're closer, then CANCEL the ACC, and coast back to at least 1 second, 3.5 is official, then tap RESUME.

Later I realized Why do that? The adaptive cruise control will automatically move you back. If it's too far back, like if you are getting ready to pass, just push on the accelerator. This till override the ACC.

Part 2

Following Distance All The Time

There is a way to have the following distance showing all the time, and the Cruise Control won't affect your speed. This way, even in local traffic you can watch that tailgating and avoid a visit to the Safety Office.

Know this about the Cruise Control feature: if you press the accelerator while it is set, you can go faster than the setting up to your maximum governed speed. Suppose the ACC is set for 40 MPH. Nothing is stopping you from pressing the accelerator and driving faster than 40 – all the way up to your maximum. Also, when you are driving above the set limit, let off the accelerator and a gentle engine retarder helps you slow down, similar to a light press on the brakes.

So, here's how to use the ACC to watch your following distance in nearly any traffic situation. At some slow speed, even as you start out from a stop light, SET the speed at the low number. The ACC should be available down to 10-12 MPH. So, it gets set for 17, for example. Use your accelerator just like you usually do, to get to the correct speed for traffic. You will still see the distance readout at 45 MPH, and you can still slow down as needed.

Part 2

Following Distance All The Time

There is a way to have the following distance showing all the time, and the Cruise Control won't affect your speed. This way, even in local traffic you can watch that tailgating and avoid a visit to the Safety Office.

Know this about the Cruise Control feature: if you press the accelerator while it is set, you can go faster than the setting up to your maximum governed speed. Suppose the ACC is set for 40 MPH. Nothing is stopping you from pressing the accelerator and driving faster than 40 – all the way up to your maximum. Also, when you are driving above the set limit, let off the accelerator and a gentle engine retarder helps you slow down, similar to a light press on the brakes.

So, here's how to use the ACC to watch your following distance in nearly any traffic situation. At some slow speed, even as you start out from a stop light, SET the speed at the low number. The ACC should be available down to 10-12 MPH. So, it gets set for 17, for example. Use your accelerator just like you usually do, to get to the correct speed for traffic. You will still see the distance readout at 45 MPH, and you can still slow down as needed.

I tried this trick. I set the cruise at 55 mph, and then increased to 60. It was pretty cool. I have also started using it more, and I am becoming more comfortable with it.

Thanks for the tips Errol.

I tried this trick. I set the cruise at 55 mph, and then increased to 60. It was pretty cool. I have also started using it more, and I am becoming more comfortable with it.

Thanks for the tips Errol.

There will be one more section tomorrow morning. These are the things I've found make driving real easy, and I don't need to visit the Safety Office so much.