ChrisM55

On my Moms 07 5.9 she is having an odd problem. When the cruise is on and going downhill the cruise surges badly. kinda bucks up and down.
We took it into the Dodge dealer and there solution was to tell her to take it off of cruise when you go downhill!!!

Does anyone have a solution to this or had this prblem before?? I want to go in with both barrels blazing at these jerkoffs!!!


Chris

coparam4x4

Mine does it too but i dont think it's as bad as your mom's. Mine is just a very slight surge. BTW my Titan did the same thing, and my wifes Honda Civic does it ever so slightly. I think it has to do with cruise being all electronic now (drive by wire). The old throttle cable style was a lot more forgiving when the computer had to make adjustments. But I could be WAAAY wrong. I'm sure someone here will let me know that.

gcssr

Chris
Your cruise control is working normal,the design is to hold the vehicle at a designated speed, thus at level speed, it will maintain set speed, going up hill it will add fuel as required to hold set speed, going down hill it works as a speed brake, to hold the set speed, it defuels and acts as a exhaust brake.
Why the dealer does not explain this I don't understand. But be assured your truck is acting normal.
My 01.5, manual, 04.5 auto, both operate this way, it is a great help when towing.
Be glad you have a group of knowledgeable people to help you.

ChrisM55

Thanks guys, this is not the normal condition. I have an 08 my brothers girlfriend has an 06 and we have a number of other Dodge Cummins in the stable. This is so agrivating that you really can't use the cruise at all except on flat ground. Just to assure myself that it was not me I drove my 08 down from Lake Tahoe on cruise about 4 days ago. It was butter smooth with none of the jerking we feel on Mom's

Chris

RRC

My 07 is HORRIBLE inthe same conditions. When cresting a hill and starting down, the boost drops. Once the boost gets to about 2-5 pounds, it starts BUCKING VIOLENTLY! If you let it do it's thing on a hill that is steep enough to kill the boost all the way (coast) it will stop bucking and jerking. But it will do it all day long at 2-5 pounds! Odd thing is, same hill, no cruise control, 2-5 pounds of boost controled by my foot, NO BUCKING!!! Haven't takin it to dealer because I new I would get a load of crap like you got!! I'll just live with it till something breaks I guess! BTW the response that says this is normal and is acting like an exhaust brake, LMAO!!!! I would like to see the look on your face the first time YOUR truck started bucking and jerking like ours does! You must be a service advisor!

kwilkinson

I have the same issue with mine... it drives me nuts A friend who also has a 07 5.9 did it too, until he put his Suncoast trans and converter in... He asked the guys at suncoast if they could explain it, and they had told him that it was related to the wide "acceptable" spec range of the governor pressure solenoid, causing low lockup pressure and causing the converter to slip if the solenoid was on the lower side of the specifide range. Brought this up with a tranny guy and he said governor pressures in these new trucks have different values from cruise on and off. Thinking about it, it seems that could be a cause. They also told him that even just a converter can fix some of the problems. Anyone running an aftermarket converter/built trans that is still having this problem?

TurboReno

Hi Chris,

You are in luck! I suspect it was the Dodge dealer closest to you that told her to take it off of cruise to solve the problem. If you look about 35 miles South of you, you will find one of the best and most knowledgeable Dodge diesel dealers in the Western US. Look into taking their Diesel 101 course for an informative Saturday morning. If anyone can provide sound advise and a fix for her issue, they can.

maxed

My 07 does it too, very annoying.

ChrisM55

God knows that is the truth!!!! Carson is so much better in so many ways!! IT was a goatrope when she took it in there so now it goes to Lithia or Carson

Chris