Re: 2011 Jeep GC Surge/Shudder/ engine miss sensation
Perhaps this helps in clarifying the situation:
I have been fighting with this issue since June (misfire sensation under light acceleration) and had the car inspected, tested by a number of engineers, and no solution has been found (applied all TSBs for driveability, which made the gearbox itself smoother in changing gear, but resolved none of these sypmtoms).
So, how does the misfire/surge/shudder sensation manifests itself?
1) In 4th and 5th gear once the torque converter has locked up
2) Whilst accelerating softly enough so that the car does not unlock the torque converter and changes down a gear
3) From 40mph+, between 2000-2500 rpm
4) In all modes, Auto/sport etc, as well as in D or Autostick (when allegedely the MDS is not operational)
5) When driving at 70-80mph, I also get a slight vibration "driving over washboard effect", particularly when driving up a slight incline with the cruise control on.
The technical explanation given to me 3 times now by the service manager who has spent hours in friendly conversations with me:
1) Connecting the laptop to the ODC whilst driving, he could see that under the conditions described above the torque converter keeps locking in/out in succession, within few hundreds of a second
2) This is driven by the MDS software, the MDS needs the torque converter to lock/unlock when engaging/disengaging
3) This command to the torque converter is given also when in Autostick mode, and it exhibits the same behaviour, although the MDS is allegedely not active
4) The issue does not occur in lower gears because the torque converter does not lock up
5) Subsituting the torque converter will not improve things as mechanically there is no slip or any loss in it at all
A Starcase is open at Chrysler to look into the issue.
Do I believe all of this? Well, who knows.
The only doubt that I have is whether the 4x4 system has any play in this at all.
The question back to you folks: do you all have 4x4 and accuse these symptoms?
The Jury has emitted its verdict though: that is the way the car is and will remain. I wanted to switch to the 2012 model, until I found out that the gearbox is exactly the same, just reprogrammed.
Appalling, as a drivetrian issue as serious as this on this type of vehicle is enough to steer customers away. I come from a history of bmw and audis, and no way they exhibilt any form of embedded mechanical imperfection. Some have issue, yes, but they do not come with a drivetrain issue as standard.
All the best,