All the newer type five speed transmission has an electronic speed sensor. This device tells your computer how fast you are going and tells your computer when to shut off. This mod disables the sensor so that your computer does not know how fast you are going. One thing I must say before I go into details is that this mod could cause your truck to void your factory warranty. Cutting on these wires is not good in the dealers eyes. The rear most connector is the one we are going to modify. ***Before you cut wires on your truck test the connector to make sure you have the right one. Discconnect the rear most plug from the tranny. This plug could be on either side of the tranny. It will be the plug that is closest to the rear end. The plug should only have 2 wires. After disconnecting the plug drive your truck to make sure the speedo does not work. If your speedo works you have the wrong plug.** Disconnect the battery and have your cutters ready to work. Unwrap the factory tape from around the connector and cut only one of the two wires. Give yourself room on both sides to splice back together. Use butt connectors to splice into the two ends and run the wires into your cab. The wires will go to a switch. We placed ours on the side of the seat but you can put it anywhere you want. With the switch on your speedometer works correctly and your truck will shut off. On the off position your speedometer will not work.. Your computer will not know when to shut the truck off. We had our test truck up to 115mph with no problems. One thing that you will notice is that your check engine soon light will come on and your ABS light will come on. Your ABS light will go on and off with the switch but your S.E.S. light will stay on until the code clears. Dont worry because your truck is not going to blow up. The switch can be thrown while you are driving. When the switch is thrown your speedo will fall to zero.. This mod will work on both 4 and 6 cylinders. This mod will not work on an automatic transmission. From what I have been told is that it will not shift.