when on cruse set on 100 to 120 km,s and i am going down a hill the truck sort-of bucks, a little surgy-bucky-jerky motion. go,s away when the cruse cuts back in. started doing this this year. no box ,pretty well stock. removed the performance enhancing stuff because of warrenty issues

 

Pretty normal as the truck cuts fuel trying to stay at the programmed speed. I'd say you're lucky if yours just started, as mine's been doing it since I drove it off the lot. Chrysler cruise controls is just garbage.

 

Same here, pretty much normal. I used to run a mileage max chip, it was worse with the chip. Still does it a little without it though.

 

Me too frank on my 07 but not too bad. Just started after 3 years from new.

 

Mine has done this from day one! It's never very bad but it is some thing I notice from time to time.

 

i guss what i need to know is if its the cruse controll unit failing or what ?. The truck still has extended warrenty and if the problem just started, is something wearing out, or did i just get lucky that it didnt happen from new, and have the dealer say ''thats the way it is''.

 

Cruise isn't failing, it's just the way our trucks work. When you're going down a hill, there's very little fuel needed to maintain speed and the cruise control will completely release the pedal in an effort to keep you at your set speed. Of course, once it's off, the turbo dies and the truck slows down again, so the cruise control gives it a bit of fuel, slightly more than it needs to regain the 2mph of lost speed, which also spools the turbo, which now means you're going 3mph faster than you want, so the cycle repeats itself. It's worse on trucks with programmers and manual transmissions, especially if they've got slop in the drivetrain.

 

My son has a 07 and has that problem and according dodge it is a problem but they don't know how to fix it. It is funny that if they put the flight recorder on to check the problem (on board computer) it goes away so it must be in the programing of the cpu. There answer is live with it until they can figure it out. I have a 03 and no problem.

 

my 03 duelly didnt do it either.

 

My Abs light was on and mine acted the same way.I fixed the abs sensor and it works great now.Apperently they read the speedoff the abs sensors.My truck is a 2003 with a quadzilla box on it.

 

What adaminak said, exactly. He described my situation perfectly. Another u-joint starting to go and I really notice it now, but it has been doing it since the beginning. The more you add to the pot, ie. tuner, heavier tires, a load behind you....the more it slows you and the harder your cruise fuels to get you caught up to speed. Just another example of a great engine in a crappy package.