This question is mostly directed at Toby99 but anyone that is experiencing the bucking/shudder/jerk condition with the 8F35 and 8F57 transmission. When you say that your vehicle has a buck/shudder/jerk condition, does your vehicle physically jerk or lurch forward when the transmission shifts? If so, what gear do you think it is shifting to? I ask because I work as an Auto Tech at an independent shop and quite often I will have a vehicle in my bay for a specific issue but I am unable to replicate the concern per the customers description. At this point I have to talk to the customer myself and sometimes have them drive the vehicle for me so I can observe what the issue is that they are having. The reason for this is that a description of an issue can mean something to one person and something completely different to another person. A couple observations of mine that relate to the 8 speed auto and transmission tuning in general. The first is that I have driven a couple of the new escapes with the 8 speed transaxle, it may be a smaller version than the 8F35 but I'm not sure, and the only shifting or transmission issue that I noticed was the tachometer bounced twice after the 2-3 shift as I accelerated through an intersection and the 2-3 shift occured as I went through the low spot on the other end of the crown in the road and that caused my foot to bounce on the gas pedal slightly. My guess is that the throttle is some what touchy and that is what caused the rpm bounce and a slight shudder feeling when that happened. The rest of my time driving the Escape, the roads were smooth and I never experienced that issue again. My other observation has to due with late model transmission tuning for most 6 speed and higher ratio count transmissions. On most newer automatics the torque convertor will lock up fairly early in the ratio spread, generally in 2nd or 3rd gear already, and that can be described as a transmission slip or shudder depending on a persons sensitivity or understanding of the transmission operation. Quite often the way the torque convertor lock up function is programed, results in the 2-3 shift then a slight rpm increase and about 2 seconds later the rpms will drop again, that is the torque convertor locking up. I have had customers who swore their transmission was slipping or described it as a shudder because the rpms dropped a second time in such short succession when that second "shift" occurred which again is the torque convertor locking up. This is a long post I know but sometimes the key to fixing a vehicle or confirming that it is in fact working correctly is understanding what the customer is experiencing in person or making sure that we are both on the same page as far as what they are describing.