Originally Posted by gc11jeepva
Just got back from the dealer who gave me a print out of STAR Case Number S1121000013 dated 9/7/11.
It addresses the lunge and discusses the driveline needing to unwind on the ignition cycle sequence. The last line is: This condition is normal and cannot be eliminated.
Still not happy that the car lunges forward but it is nice to finally have some info on the issue.
I don't buy that. With a live rear axle and a long drive shaft that can happen following a stop. (GM CK Trucks with a long bed for example) But the JGC has IRS (Independent Rear Suspension). As a result, the source of the problem that can exist with a live rear axle simply doesn't exist when the vehicle has IRS. Even then the problem doesn't manifest itself on an engine start. It only occurs within a minute following a coast down to a stop.