Noticed my 2007 GC SRT8 likes to roll backwards when on a hill when in drive (any grade above 15% seems to work). I noticed this last week when on an approximate 25% grade and took my foot off the brake. It's a good thing nobody was behind me, because the vehicle kept rolling untill I hit the brakes. Went to the Jeep dealer the next day, they were not aware of this problem. I then showed the problem to the technician on a 10%-15% grade and sure enough it rolled backwards until it decided to stop. This is my third JGC and none of the others did this. The technician mentioned the SRT8 has a NEG (I hope thats the correct spelling) Mercedes transmission and this is common. So off to the Mercedes dealer I went. You can guess the answer I got (not common). Has any one else experienced this problem?

Noticed my 2007 GC SRT8 likes to roll backwards when on a hill when in drive (any grade above 15% seems to work). I noticed this last week when on an approximate 25% grade and took my foot off the brake. It's a good thing nobody was behind me, because the vehicle kept rolling untill I hit the brakes. Went to the Jeep dealer the next day, they were not aware of this problem. I then showed the problem to the technician on a 10%-15% grade and sure enough it rolled backwards until it decided to stop. This is my third JGC and none of the others did this. The technician mentioned the SRT8 has a NEG (I hope thats the correct spelling) Mercedes transmission and this is common. So off to the Mercedes dealer I went. You can guess the answer I got (not common). Has any one else experienced this problem?


no way, actually on a 15% incline my car will slowly crawl up w/ my foot off the throttle or brake - go to another dealer.

There are quite a few factors the detemine whether the car stays still in drive or not on a grade.

Line pressure
Torque converter fluid pressure
Torque converter specs vane to stator ratio and stall speed
temp
fluid viscosity etc.
RPM


I have had several cars that would even sometimes stay total still on a grade but at other time the same car would move backward.
Transmission slips as mostly known are the clutches not maintaining proper engagement due to line pressure. At idle in drive it is a function of the above items and not really a big concern. I would suspet the torque converter is a little "looser" in terms of vane alignment stator to rotor then base cherokees and this is what you are seeing. In a looser config or higher stall speed the torque conver doesnt apply significant line pressure and or stator speeds until a higher rpm.

If you were seeing raised rpms during shifts or erratic shifting then I would be concerned.

My 07 is the same moves abit down the driveway in drive.

Thanks for the feedback! If some owners are not experiencing this problem, I would like to be one of them. The problem is not a gradual roll backwards. It rolls as though in neutral. Off to the dealer with some of the feedback.