Anyone else find cruise control to be pretty much useless, except for perhaps following a line of cars when you're stuck in traffic? My usual would be to set it to 8 or 9 mph over the limit, however the way it slows down around even the slightest curve makes it unusable. Same thing when the speed limit changes, I'd rather reset it myself. Same category as rain sensing wipers.

 

Can't you disable that? I was able to on my '21

 

Didn't know you could. Thanks for the heads up.

 

I can't remember what it's called but it was buried in one of the menus. Sorry I can't be of more assistance but I'm sure someone will chime in with the name of the setting.

 

Interesting topic as I really dislike the cruise on my 2021 for the same reasons. I'm a tech moron so I didn't even look to see if it can be reset to defeat those issues.

 

I think it may be called "route based speed" or something similar

 

On a freeway in Nevada (2 lanes my direction) while passing a semi with someone in front of me and someone behind the speed limit on my HUD went from 65 to 25 and then back again a minute later. Fortunately I wasn't using cruise at that time. The idea of it automatically slowing down or braking is good, but the implementation, at least in 2018, leaves a lot to be desired. I also had it start a panic stop at 35 mph. Luckily no one was behind me. I've turned off all that stuff.

 

Definitely disable "Route Based Speed Adaptation" and "Traffic Sign Assist>Adopt Threshold." I feel like the "Active Lane Keeping Assist" is good enough to keep enabled. IMO this configuration is actually a pretty damn good cruise control, especially for a legacy car company.

 

agree. It's totally useless for me. I have owned mine for nearly 5 yrs now and I have yet to use this Cruise control feature.

 

Driving across Texas on the Interstate was particularly annoying. Speed limit is 80 MPH and I set speed to a reasonable margin over that. Every time I'd pass a frontage road with a 35 MPH limit the car would jam on the brakes and I'd have to scramble to stomp the gas peddle.

Finally found the option for the Traffic Sign based limit change and turned that off.

The feature was great while driving in Europe during my ED tour and likely saved me countless speed camera tickets where I frequently didn't see the sign posting limit change.

My 2018 doesn't have the Route based adoption feature, only the Traffic Sign feature, and with that turned off cruise control works pretty well for me, particularly in traffic. I'll set the Distronic to some reasonably high value and the following distance short enough to keep all but the most aggressive lane changers from cutting in front of me and then the car will adjust to the flow of traffic quite well.

When the road is open, my only complaint is that it never goes into eco mode or coast mode like it would if you are driving manually. It also holds the speed down hills. So as a result, driving manually you can do a little better on fuel mileage. But not a lot - at least in my non scientific tests.

 

That's a fair point on the traffic sign assist...I'm sure it prevents a ton of tickets in Europe where they have speed cameras everywhere...whereas on US freeways it's a pure liability.

 

Folks should really read the owners manual before complaining. As said above, all these adaptive route settings can be turned off. I turned off the speed limit adoption, because as others have said, I don't find it useful in the USA, but I also did ED and there it was very helpful. Actually worked quite well in Europe. I just came back from a month in Europe. Had an Audi A6 rental with driver assistance, but it was terrible compared to the Mercedes system. At times it misread speed limits or didn't see them at all, suddenly slowing down for no reason and such. Might have actually gotten a speeding ticket in Switzerland on the last day, somewhat because of it.

 

Just got back from a long road trip and used it quite a bit. (All the "nannies" are off.) It's definitely best on a straight highway, but other than slowing a bit too much on curves, I found it a big help. Especially in areas where I was getting "There's a speed trap ahead" messages constantly. On the long banked curves, I just got used to pressing the gas pedal to "suspend" and maintain speed until the road straightened out again.

I tried using the auto-steer, but that's not real useful on actual highways. It worked great when the striping was perfect, mainly stretches that had been recently maintained. For the rest, I could just hear an engineer yelling, "in Germany vee don't allow faded striping!" as the car aimed for the guard rail.

 

I've found that the steering assist works OK on Interstate highways but not so much for 2-lane state highways that curve around some mountain roads here in So Cal, at least not unless you're really paying attention for the corners. The amount of additive steering input just isn't sufficient for the extra force required in tighter radius corners.

It would probably be OK in some flatter areas where the corners tend to be larger radius turns.

But even on the Interstate I keep a pretty good eye on it because as noted it will head for the hills if the striping isn't well marked and other than the indicator turning amber doesn't give me any audible beeps as a heads up that I've got the helm.

 

I just came back from 10+ hour road trip through Florida and I love the cruise control setup. I have everything enabled except the dynamic speed limit adoption based on posted signs. It's really nice to just keep your hand resting on the steering wheel while the car maintains a safe distance and stays between lanes. You can even have it change lanes for you by holding down the turn signal stalk. Very relaxing driving experience for long road trips.

 

Never really used CC, I trust myself better.
I turn it on occasionally to make sure it's still working.

 

Due to a calibration error by a dealer in Nashville I had to drive between Nashville and Dallas with the car totally old school, no cruise of any kind.

When driving 10 to 12 hours in a day with only the occasional stop for fuel and grub/coffee, your right foot will tire and even switching to throttle with the left foot starts to get old.

Really happy when the dealer in Dallas got it all sorted back out again and I was able to make the rest of my drive from Dallas to San Diego with full distronic features available.

We've loved every trip taken with this car, it really eats up the miles. Getting the Flowers for Algernon treatment for the lobotomized LED headlights helps a lot too when driving on the highway at night.

 

The first thing I did was read the manual before starting the thread. There is not one word about adaptive settings in the section about cruise control. I realize they don't want a 1,000 page manual, but that is a clear oversight, so I turned to the forum for help. Thank you all.

 

It's most certainly all documented. On page 187 is the Active Speed Limit Assist and on Page 200 is how you turn it off, then on page 188 is the route-based speed adoption and how you turn it off on page 189. The owners manuals are available online as PDF, so you can even search them.

https://www.mbusa.com/en/owners/manuals