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Discussion Starter #1
Some thoughts on the adaptive cruise control, it's absolutely my favorite feature, but there are some caveats, in my opinion...

The adaptive cruise control works so well, it can be tempting to think of this as an autonomous or at least a semi-autonomous vehicle. I have been amazed to see the car slow down to a full stop behind a vehicle in front of me coming to a well controlled full stop, and then pick up and follow it when the car resumed progress [had my foot hovering over the brake pedal all the way tho ;-)].

But... however tempting it is to think so, this isn't a self-driving car, and you need to disengage cruise control before entering corners, and before entering town limits lest you find yourself traveling far too fast for the environment.

If you're initially following behind another car that's doing the right thing, it can be tempting to think your car "knows what to do", but it doesn't, it's just mirroring the sentient driver ahead, and your car will take off and go way too fast the moment they exit the lane in front of you. I think it's also prudent to disengage cruise when in thick aggressive traffic where people are cutting in and out between lanes or in stop and go traffic. I also like to run mine with a longer following distance to give more margin for system "thinking" and for my intervening if it makes a mistake.

This system is a great advance over old-style "dumb" cruise control and I am tickled to have it, but it's still just an advanced cruise control and it isn't foolproof. You need to be mindful of the system limitations and remain the executive in control at all times. There are some similar caveats in the manual, but these are my two cents! ;-)
 

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Safety wise, it's fantastic.
But in real world driving, I find it a bit of a PITA.
Driving on separated 4 lane highways (interstates), using it makes passing difficult and actually more dangerous.
As you approach a slower vehicle in front of you, even set to the minimum 1 bar separation, your car will begin to slow down.
In order to pass the slower car in front, you are forced to either pull out early to maintain your set speed, or deactivate the cruise temporarily in order to overtake.
If there is anything but very light traffic (rare), I just don't bother with the adaptive side of the cruise and more often than not use regular cruise.
 

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This is what I thought until I realized if I press the gas pedal it ignores the adaptive cruise and passes without slowing the vehicle. Once the pass is made release the gas pedal and adaptive cruise resumes. If you lift all the way off the gas pedal before switching lanes to make the pass then it will slam on the breaks making the pass dangerous.
 

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I know that will work.
What I don't like is that I have to start using the gas and anticipating and planning the pass way behind the vehicle I am overtaking.
 

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Discussion Starter #5
I actually haven't had any issues with it when driving on I-95 (limited access road with 4 lanes in each direction and usually moderate traffic in this area), whether sitting behind a car or passing. I pretty much drive with the automated cruise the same way I drive manually on I-95, and it hasn't been getting in the way. I do pay less attention to my speed with the auto-cruise. I used to try to drive exactly 75mph at all times, and was more active with changing lanes to pass to try to maintain that more rigorously. Now as long as I am not going too slow, I am more content to stay in my lane and let the system manage the fine points of throttle control.

Whether manual or auto-cruise, I tend to leave about 5-6 car lengths between me and the next vehicle, and when passing, I just look that it's clear to get into the faster lane to my left and do so when it's safe to move over. Then I'll just stay there until I get past the slower car or cars in that lane...with the exception of speeding up a little more with either the gas pedal or a bump of the cruise button to add 5mph to get past them sooner if a guy behind me is wanting to go even faster... seems to work okay for me so far, I haven't noticed anything in terms of danger or unusual braking or acceleration.

I have had a couple of concerning situations on Route 1, but those were due to slower cars merging in front of me in thick traffic, and my own car seemingly still tracking the car in front and speeding up before I intervened. I am going to use a longer following distance on Route 1 than I have been doing
 

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Discussion Starter #7
Safety wise, it's fantastic.
But in real world driving, I find it a bit of a PITA.
Driving on separated 4 lane highways (interstates), using it makes passing difficult and actually more dangerous.
As you approach a slower vehicle in front of you, even set to the minimum 1 bar separation, your car will begin to slow down.
In order to pass the slower car in front, you are forced to either pull out early to maintain your set speed, or deactivate the cruise temporarily in order to overtake.
If there is anything but very light traffic (rare), I just don't bother with the adaptive side of the cruise and more often than not use regular cruise.
Not sure if I can follow what's going on precisely, but if you approach a slower vehicle from behind, your car needs to either slow down or switch to another lane, no matter who's controlling it. If there's a big difference in speed, and you have it set for minimum following distance and try not to change lanes until you're right on top of the vehicle in front, then it would probably roar right up on the slower car and then need to brake suddenly. if this is what's happening, then I don't think it's a system malfunction, it's doing what you set it to do and dealing with the road situation that it's in.
 

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Thoughts? Not a fan at all. Same is true for all of the other supposed “driver aides”. Just a bit of false security in my opinion.

Driving a car is the most dangerous thing that any person can do. Yet we all do it everyday without much consideration of this fact. No ammout of computer wizardry is going to change this reality. Instead of relying on a digital nanny perhaps people should be properly trained on how to drive a car again.

I’d rather take my chances amongst average drivers who are in control of their vehicles versus a bunch of terrible drivers cruising blindly along in what they deem to be some sort of autonomous shuttle craft. Speaking in generalities of course.
 

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I am very much a driving enthusiast and enjoy driving myself but definitely will be looking to get adaptive cruise at least on the next late model car purchase I make. Especially for stop and go traffic (for those systems that can handle it). With any system you learn to understand it's limits and adapt accordingly. I absolutely do not subscribe to the theory that these technologies are detrimental to general driving safety. Bad drivers yes, technology no.

I've always looked forward to the day where in heavily congested areas - such as our local bridge tunnel system which is backed up for miles every single day, simply due to drivers slowing down for the tunnel - that cars will be autonomously forced through the tunnel at 75mph. Yes you and I may not be the cuplrits, but no amount of driver training will stop those prone to it from slowing down to 35 and backing up traffic for miles - despite the current "Maintain 55" signs posted all over the place which humans ignore. A so equipped autonomous system could get traffic through the tunnel faster and more safely then any mob of humans, at much higher density due to quicker and predictable reactions. This scenario is decades away since cars not so equipped will have to be outlawed from these areas. 2-3 decades at least maybe?

If you told me the same forced system would be implemented in a low congestion area, I would rally against this - I expect in our lifetime there will always be public roads we can DRIVE on!
 

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I know that will work.
What I don't like is that I have to start using the gas and anticipating and planning the pass way behind the vehicle I am overtaking.
I don't think having three car lengths is, or should be, considered "way behind" when attempting a safe lane change at today's freeway speeds. I would normally be allowing at least this much distance between my car and the car I am passing anyway. I agree, however, that this can only be done on the open highway when you are not in congested conditions.
 

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I know that will work.
What I don't like is that I have to start using the gas and anticipating and planning the pass way behind the vehicle I am overtaking.
True but you have two options. 1) Anticipate the pass and switch lanes before your follow distance zone is entered to avoid the vehicle braking. Or 2) Press the gas pedal to enter inside the follow distance zone allowing a later switching of lanes without braking. But this will also require anticipation.

For this NOT being fully autonomous driving, I love how well the Subaru adaptive cruise control works. I've driven the entire East Coast, Canada to FL using adaptive almost the entire way. It's fantastic. The one thing I didn't like was how aggressive it accelerated after switching lanes or after the vehicle ahead moves over out of the way. To remedy this I lowered the cruise aggressiveness in the settings menu. It's almost perfect now. The only time on the freeway I drive manually is in bumber to bumper traffic jams because I can do a better job holding one speed to save gas and not be at mercy of the erratic accelerating driver ahead.
 

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Discussion Starter #14
True but you have two options. 1) Anticipate the pass and switch lanes before your follow distance zone is entered to avoid the vehicle braking. Or 2) Press the gas pedal to enter inside the follow distance zone allowing a later switching of lanes without braking. But this will also require anticipation.

For this NOT being fully autonomous driving, I love how well the Subaru adaptive cruise control works. I've driven the entire East Coast, Canada to FL using adaptive almost the entire way. It's fantastic. The one thing I didn't like was how aggressive it accelerated after switching lanes or after the vehicle ahead moves over out of the way. To remedy this I lowered the cruise aggressiveness in the settings menu. It's almost perfect now. The only time on the freeway I drive manually is in bumber to bumper traffic jams because I can do a better job holding one speed to save gas and not be at mercy of the erratic accelerating driver ahead.
Thanks for that, PearlWhite - I already like the way it works on I-95 just fine. On Route 1 though, which has much thicker traffic and a lot more dynamic lane changing going on by aggressive drivers, along with people entering and exiting the roadway from the shops lining the road, it hasn't been 100%. If there's a setting in the main info screen to reduce the aggressiveness of throttle used when changes occur, that would be just the ticket for Route 1 :).
 

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On the Interstates I set it at 5 above the speed limit and go with the flow. My eyes and my foot are always at the ready, just in case.
 

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Discussion Starter #16
So tailoring the Adaptive Cruise Control settings (besides following distance, which is right on the dedicated steering wheel buttons) is covered in the EyeSight owner's manual, page 103 forward in the 2019 edition. It shows there that the default acceleration level for adaptive cruise is the 3rd highest of 4 possible settings. Thanks to @PearlWhite, I have found that and set it to the lowest setting dubbed "Eco", which they say also gives the best fuel economy. Let's try that.
 

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Discussion Starter #17
On the Interstates I set it at 5 above the speed limit and go with the flow. My eyes and my foot are always at the ready, just in case.
Reading through the EyeSight manual's 26-page main section on Adaptive Cruise, there are numerous caveats, which I think are helpful to review because they are highlighting limitations of the system - good info! They say there that it's intended for use on limited access roads, and among situations that are known trouble areas, they list having a vehicle cut closely in front of you, which I have observed personally. It may be that even if I set the following distance long and tune it to accelerate gently, I am better off just not using it on Route 1. Route 1 isn't city traffic, but in the stretch I drive, it is busy and dynamically changing - which leaves less time for the system to respond and me to intervene if needed.

With all these EyeSight subsystems, while there may be info flashing on the screen, my initial reaction is to evaluate what I see in front of me if I hear a beep in normal driving. I don't think it pays to stare at the info screen and read it when you may have a fraction of a second to respond and correct the vehicle. Then if things are okay ahead, I glance down to see if I can read what the warning was.
 

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Masssubie, I agree there are times it's best to drive without it. Orlando was horrid with so many ****** drivers cutting me off even with the closest follow distance I decided to not use adaptive to avoid it braking constantly.

Currently in Tampa area now and during rush hours I don't use it, again too many idiot drivers cutting in front with inches to spare, and I'm not a slow driver.

But for more open freeway driving it's great.

If you watch some LA Tesla videos in autonomous mode you'll notice the same issue with asshats cutting in front forcing hard braking. Even in "Mad Max" mode. If there's an inch, they'll take it.

I've only lowered my settings aggressiveness one position so far and am happy. I was afraid to go all the way down to ECO mode since I don't want to lag when a car moves over. Let me know what setting you end up with.
 

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It is my favorite feature on the Forester. Most of the time on the friendly light traffic road conditions I encounter it's great.

It's not perfect when surrounded by crowded high speed multi lane traffic but I wouldn't expect any system to anticipate some of the poor decisions other drivers make. In that situation I switch to defensive mode and don't want to have any systems making decisions for me so I just turn it off in those situations.

It also works great when traffic is in that stop and go almost traffic jam situation. You know where people speed up to 40 then slow back down to 5 like a giant slinky. The combo of adaptive cruise and CVT have changed my opinion of the usefulness of automatic transmissions. If I was forced to drive in these conditions frequently I would consider getting another car with an automatic transmission or confiscating this one from my wife.
 

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Discussion Starter #20
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The combo of adaptive cruise and CVT have changed my opinion of the usefulness of automatic transmissions. If I was forced to drive in these conditions frequently I would consider getting another car with an automatic transmission or confiscating this one from my wife.
I have owned a Honda Si with a precise short-throw shifter and nice light clutch and loved driving that car, but I wasn't doing long daily commutes including what's often 5-10 miles of heavy stop and go traffic, as I do now. You couldn't pay me to drive a stick on my present daily commute, I don't care what car it is. Auto transmission, even without adaptive cruise, makes the situation soooo much easier.
 
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