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Message: [QUOTE="me2, post: 342290, member: 3825"] Just so that there is no mis interpretation, I better explain a few things. The 6R140 and others like it shift with 2 sets of controls. The first is the valve body. In a Superduty a mechanical cable connects the column shift lever to a shaft in the valve body. When you move the lever, the shaft selects various gear options such as Park, Reverse, Neutral, Drive, etc by moving the valve body shaft and changing the oil flow in the valve body. However, nothing except limp mode works by the valve body alone. Once the valve body position is selected, the transmission control unit takes over and sets the line pressure and controls the various shift solenoids, which control the oil supply to the various clutches. The TCU knows which shift position the driver has selected via a sender connected to the valve body shaft. The valve body makes oil pressure pressure available to the various clutches and shift solenoids for the option selected (Park, Reverse, Neutral..) and its up to the TCU to provide the right pressure and volumes to the clutches at the right time to effect good transmission operation. So when HRT asks me about using a servo on the valve body, he is speaking about replacing the column shift lever and cable with an actuator that can be controlled electronically to select Park, Neutral... Drive. Even though I am using the column shift lever and the driver is manually selecting the "gear", ie Park, Neutral... Drive, when the driver puts the transmission in Drive, my transmission controller will still have full control over the operation of the transmission for all the forward gears. It won't be able to put the transmission in Reverse, because that requires a valve body shaft movement. But it can shift 1st, 2nd... 6th, anyway it desires. Thus the need for the console shifter. Within the Drive option will be several sub options, some of which will allow the driver full manual control over gear selection. The console shifter will allow the driver to command an upshift or downshift in those modes. You guys probably knew this already, but there it is anyway. [/QUOTE]