Cruise Control not so controlled

[bora]

How well does your cruise control hold the set speed when going down a steep hill?

Mine is very loose, it will allow a good 5-7 mph OVER the set limit.

Is my cruise control broken or is this normal?

Bora

[Road Kill]

Mine holds it right on setting. smile.gif

[dmaxstu]

My cruise control is very accurate. However on my last long trip it ceased to function on one occasion so I stopped and re-booted and was fine after that. Stu

[hdmax(mike)]

If you are not in tow/hual mode the cruse will allow the truck to gain several mph on a steep down hill grade. All automatics have this problem
It is normal. On the other hand, when in tow/hual this transmission will do everything in its power to control this. No other light truck has this.

[Kennedy]

We ran 80+ on some declines with the cruise set no higher than 74mph towing out to MT. Of course, these were hills where you could see what was coming etc.

The biggest annoyance I see is that the cruise will let you drop to 2mph below set point before coming roaring back in.

[SoMnDMAX]

IMHO, We shouldn't be complaining. Those of you that never got the chance to experience the cruise control's actions on the early 2001 trucks have nothing to complain about.

At some point the cruise and engine braking will not be able to overcome the effects of gravity, and you'll need to use the brakes.

[bora]

SoMnDmax,

In all my other cars, cruise control will and does apply the brakes to maintain speed. Does the DMAX cruise control not use the brakes?

Bora

[Lawnboy]

In all my other cars, cruise control will and does apply the brakes to maintain speed. Does the DMAX cruise control not use the brakes?


This is a new one to me! What are your "other" cars, and what do they use to actuate the brakes? Do your brake lights come on?


I think the "looseness" that you are referring to in your original post is the "FIX" for shift business while in cruise. Previous trucks were constantly shifting into and out of 5th to maintain EXACT mph. They loosened it up a bit to prevent this.

All MY other cars are VERY accurate and will only speed up while going DOWN a VERY steep hill.

[mdadgar]

Bora, the cruise control doesn't apply your brakes in any other cars. Really. It doesn't.

Go look under the console for a brake application actuator. You won't find one.

- Mark

[bora]

Mark

I guess you may be right, with the 4 cylinder engine in my M3, when you get off the gas it feels like the brakes are applied though :)

I am sure you know the feeling.

Bora

[Colorado Kid]

My wife's Honda Odyssey has "grade logic" which will under some circumstances downshift by itself while descending hill, but it absolutely won't do it with cruise engaged. Start down a hill (say I-70 west of Denver) and it'll run to the set speed + a whole buch coasting in high, just click the cruise cancel button and it down shifts immediately...I guess the Honda engineers don't think you should use cruise in the hills. I'm impressed enough that the Allison in tow haul mode will downshift with the cruise on. I'm not familiar with any vehicle on which the cruise control has any authorithy with the brakes...except new Mercedes S class, which have a station-keeping cruise control which maintains distance from the vehicle ahead. (For the price it has to have some trick up its sleave!).

[mattb5150]

I believe most manufacturers suggest that cruise control should not be used in hilly terrain and in windy conditions, at least this is what my 1993 Chevy 6.5L owners manual states.

Matt B.