I have owned several vehicles with this feature and while the Defender is currently my favorite vehicle of all time I must say that the adaptive cruis control is terrible. Mine constantly surges forward, then hits the brakes and surges again. It will make you want to barf. Anyone else have the same issue? Maybe it is something that needs repair. Just seems like bad coding to me. Infiniti, BMW are smooth and you can’t feel anything unless someone taps their brakes in front of you.

 

Mine is not as smart as I would like, but I wouldn't say terrible. I suspect that running ACC on less than 3 'bars' distance from the front vehicle gives it less of a time window to react and hence the braking is harsher. I also find it struggles with tighter corners which, again, I can understand.
It would be interesting to learn where other manufacturers source this tech from, as I wouldn't be surprised if this is a system developed by a supplier rather than the manufacturer themselves.

 

Are you running the 3.3.0 SW update? It really improved the ACC reaction time for my car. Nothing groundbreaking but I feel it is now much less jerky and much smoother. FWIW, I usually run it with one bar distance if in very slow/stop and go traffic (otherwise you will always get the occasional jerk cutting in front of you). When in higher speeds I use a mix of one and two bars. If I see upfront that traffic will slow down (or sometimes come to a halt) very fast, I increase to two bars, otherwise it will sense too late and will grab the brakes like there is no tomorrow. I would not buy another car without this feature, after having it in my DD. It is night and day if you drive a lot in traffic and highways. It is still unbelievable to me this is not standard for all Defenders above the SE trim.

 

I am running 3.3 software. I will try to increase the distance to two or three bars. My other vehicles with this same feature were flawless. It seems ok a slower speeds but at 75-80 on the interstate it is terrible.

 

I’ve had ACC in three different cars and my Defender is easily the best. Don’t know why yours feels different, but mine is fantastic. Not jerky at all. I usually leave it on two bars, but even on one it’s fine. It’s a lot smoother than my lead foot.

 

I have had it on my last two cars and wouldn’t order one with without it. To me it’s as an important of a safety feature as airbags.

 

it is a bit white knuckle compared to some others I own when you come up on a line of stopped cars. I tend to run further back than a few bars as well, but will get some big experience on how it works next month when we do our 2200 mile round trip road trip for Christmas.

 

You run the minimum 1 bar distance while doing 80mph?

 

I have not had any issues with stopping it is mainly when I have the cruise set on 80 and following a car doing say doing 78 for long periods of time. It is like the computer taps the brakes too often and then as a result falls behind and accelerates to catch up. Constant surging and slowing. Past vehicles were much smoother in this condition. Maybe mine needs adjustment or something.

 

I have to agree it can be jerky, but I find changing the 'follow me' distance (number of bars) can help, as can adjusting your set speed. All part of the freeway driving experience. TBH, while I love the ACC (and LKA for that matter), I think in the long run it makes you a complacent driver.