3.0 D4 CC special feature - go faster with go slower button

[Graeme]

Holding the decrease speed button whilst the vehicle is travelling faster than the set speed will increase the set speed rather than decrease it.

EG set speed 114kph (real speed 109), vehicle gets to 118kph down-hill, hold decrease button and watch cruise setspeed go 116, 118, 120 (I cancel at that point!). Absolutely repeatable.

I don't think LR would have intended this special feature and LR from the programmers up need a good lesson in program/function testing. It really isn't that funny.

[Neil P]

Interesting point.
With the D3 , I don't like the way it gathers speed in c.c mode
when rolling down hill , more so than if the c.c is shut off !
I cancel it , then resume on the flat ....... it's rubbish , as is
the speed maintenance ( or lack thereof ) going up hill.
Lots of quirks in the system so just use the skinny instead.

[gps-au]

Try putting the gearbox into "Sports" mode. (its a bit better - on a D3)

[Graeme]

So the 2.7's CC is as bad as the 3.0's. I was hoping mine's behaviour was new and thus stood a chance of being fixed.

[AnD3rew]

In my D3 the other day with CC on, and hit a bit of a hill just as an overtaking lane started, the hill slowed me down a little and the CC started accelerating the car, just as another car was overtaking me, so I pushed the go slower button a couple times to let him get past but it made me acelerate even more which enraged the person trying to overtake me, and got me into an argument with my missus who wouldn't believe that I wasn't trying to race him.

[DiscoSaffa]

Sorry to throw the cat amongst the pigeons here...... Although I don't get to use the CC on my D3 too often I have just had opportunity to use it on the 750km of Pacific Highway between Sydney and Ballina.

To my mind, it performed really well. The go faster and slower buttons doing their thing as they are supposed to, and on all but the steepest hills, it maintained speed very well.

Perhaps my expectations are not as high as some as it is my first vehicle in 10 years with CC, but to those complaing about speeding up on downhills, and slight slowing on uphills before the change down, bear in mind you are driving three tons of metal, plastic and leather, that has some serious momentum and inertia..... it takes a pretty sophisticated CC system (ie one that operates the brakes) to slow that sort of weight down on steep hills, and without the benefit of eyes, I reckon it does pretty well on the hills......

In situations like over taking (or the one you mention AnD3rew) I reckon it is a far better bet to just hit the brake pedal or plant your right foot and do things manually...... rather than trying to find one of 4 tiny buttons on the steering wheel that don't come as intuitively to hand as the brake or accelerator pedal does to foot.....

Just my two cents worth

[CaverD3]

Happy with how CC works on my D3.

Interesting to see if the compaint is conistent for all D4s.

[chuck]

The cruise control on mine works brilliantly & my speedo is spot on.

Regards

Chuck

[Jesse B]

Just come back from almost 3000 km trip from Albany to north of Leonora, via a whole swag of different roads - and even including a few long and reasonably steep hills (well, for WA at least). Could not complain about the CC function on my D4. Most I saw it over or under set speed was 3 kph, and that was both over (going down to a river crossing on a highway at set speed 116 kph) and then under (going up the opposite side of same crossing). Didn't try the decrease speed button when over set speed (as per Graeme's original post) so cannot comment on that behaviour.

Checked my speedo with hand-held (and accurate) gps and found it reads a consistent 4 kph above real speed, all the way from 60 kph to 120 kph.

[Graeme]

Perhaps my expectations are not as high as some as it is my first vehicle in 10 years with CC, but to those complaing about speeding up on downhills, and slight slowing on uphills before the change down, bear in mind you are driving three tons of metal, plastic and leather, that has some serious momentum and inertia..... it takes a pretty sophisticated CC system (ie one that operates the brakes) to slow that sort of weight down on steep hills, and without the benefit of eyes, I reckon it does pretty well on the hills......

There's plenty of grunt to accelerate up the steepest of hills so loosing speed is not due to that. Pressing the speed increase button a couple of times does the trick, but then have to decrease at the top.
Overrun does not totally cut throttle, as evidenced by looking at the instantaneous fuel consumption. Cancelling CC slows the vehicle more and instantaneous fuel consumption becomes zero. I consider that LR has implemented a minimum CC throttle, possibly trying to prevent a jerky re-opening of the throttle, at the expense of maintaining the set speed.
My TD5 D2's CC would prevent downhill runaway much better than the D4. Cancelling its CC made no difference so I assume CC cut fuel when too fast.

Its very annoying having to constantly adjust CC to try to maintain a constant speed when travelling in the proximity of other vehicles on freeways. The 3.0's very sensitive throttle and quiet engine makes it quite difficult to maintain anywhere near a set speed in undulating terrain.