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Overland-North 05-14-2011 07:14 PM

ACC and towing?
Hey gang. I recently bought a new (to me) tent trailer and have towed it twice in the last two weeks. I'm new to towing and just read in the manual that the adaptive cruise control is to be turned off while towing but it doesn't specify why.
Can anyone shed any light on this for me? I'd appreciate any info. We're driving across Canada and back this summer and the cruise would be beneficial to say the least.


Technosavant 05-14-2011 07:17 PM

Re: ACC and towing?
Probably because the extra weight means that not only is it rougher on the powertrain when accelerating, but especially because it can be dangerous when decelerating. If you're depending on ACC to keep you from rear-ending something, add on another ton or so back there and the system might not compensate.

ColdCase 05-14-2011 07:23 PM

Re: ACC and towing?
Regardless, you still should be able to use the non-adaptive cruse control.

Overland-North 05-14-2011 09:12 PM

Re: ACC and towing?
Ha! I have regular cruise too! Hagahaha. It seems as though I keep finding things out about my Jeep every week. ;) So it shouldn't be an issue using regular ol' cruise while towing?

bobkbusch 05-15-2011 12:25 AM

Re: ACC and towing?
I towed my trailer with 2 ATVs, around 2200lbs, using the ACC just to see how it did. I used the number 3, or farthest following distance, setting. I was towing at approx 65 mph on relatively flat highway. It worked perfectly...

mjw930 05-15-2011 09:10 AM

Re: ACC and towing?
While using cruise while towing a light load may be fine, if you are towing anything that requires trailer brakes you should NEVER use cruise control. Consider that you have 2+ tons of additional weight behind you and all the cruise will do is decelerate, it won't activate the brakes in a manner that will activate the trailer brakes so you lose that level of braking. In a rapid deceleration event, without your trailer brakes, you will be in a world of hurt.

Conventional wisdom is that cruise control and towing are mutually exclusive activities. Chrysler deactivating ACC when towing is correct and anyone who uses cruise while towing any significant weight is tempting fate IMHO.

Deserthucker 05-15-2011 09:28 AM

Re: ACC and towing?
I drive a 120 ton road train 3trailers with cruse control.
And tow with my WJ a trailer 2.5t with cruse control no dramas.
Would not do it in traffic.
But ACC in the WK2 does use brakes when needed.

Knightrider03m 05-15-2011 09:40 AM

Re: ACC and towing?
I don't even know why you would want to use CC while towing. But post number 2 is the best possible answer.

ColdCase 05-15-2011 09:58 AM

Re: ACC and towing?
You use CC while towing as you would use it any time, for me as a safety device to keep the speed from creeping up on me. I haven't towed with GC, but my RAM truck diesel hardly notices a trailer unless I am way heavy. Very minor throttle input needed on up hills. Since you need to be alert and anticipate speed changes while driving in traffic (due to the trailer reaction times), I wouldn't use CC there.

mjw930 05-15-2011 10:35 AM

Re: ACC and towing?

Originally Posted by Deserthucker (Post 415118)
I drive a 120 ton road train 3trailers with cruse control.
And tow with my WJ a trailer 2.5t with cruse control no dramas.
Would not do it in traffic.
But ACC in the WK2 does use brakes when needed.

Good for you but I'll assume your "rig" is designed for cruise with properly integrated systems, passenger vehicles with off the bumper hitches are not.

It also truly scares me that someone piloting a 120 ton road train has become so complacent and is arrogant enough to think they don't need to be 100% focused on the task at hand that they would even consider using cruise control.

Cruise and ACC are two entirely different animals and although ACC uses the brakes I'm pretty sure it DOES NOT use them in a manner a passenger vehicle's brake controller can detect. Most brake controllers initiate the braking by detecting the brake lights through the manual switch that's part of the brake pedal. ACC activates the brake using the computer so even though the brake lights may come on they aren't activated by the microswtich the brake controller uses as a trigger.

Deserthucker 05-15-2011 10:48 AM

Re: ACC and towing?
Arrogant huh, you have some nerve

Cruise control is only a device to maintain speed.
On a long straight road like we have here, no problem.
On bending roads up and down hills then no.
I turn it of when approaching Perth hills.
But from Kalgoorlie to Northam 500km almost completely straight flat road then on cruise.
With cruise on I am more alert less tiered the without it.
Like all things they have their place and time.

ColdCase 05-15-2011 11:21 AM

Re: ACC and towing?

Originally Posted by mjw930 (Post 415192)
... passenger vehicles with off the bumper hitches are not....

I dunno where you are getting your information, dunno where the off the bumper hitch was mentioned. The comment seems to be misleading and somewhat pompous, but its hard to tell from postings.

I wouldn't seriously tow with a vehicle with off the bumper hitches, and the factory CG is fully integrated with the vehicle and rated to 7500 lbs which is far from being off the bumper, I think. You are guessing about how the AAC works in relation to the brake and fully integrated brake controller, and may be completely wrong. Do you have the tech data reference by any chance, not that I'm skeptical, I just want to learn the details.

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