This is a NEW REAR Driveshaft Replacement that fits all the following stock 2004-2008 FORD F150 & Lincoln LT WITH 139" WHEEL BASE. The original OE Driveshaft has staked in style u-joint which can be serviced but are very costly from the dealer and are very difficult to install.They require a special tool to remove the old u-joint.this kit comes with shims to make the new joint install properly and will most likely cause vribration problems due to the fact that the u-joints will not seat the way the original joints did. Our shaft comes complete with serviceable and grease-able u-joints and is a fully balanced witch eliminates the need for the need for round dampener on the transfer case yoke. This NEW Driveshaft is complete, balanced and ready to install. It's measurement is approximately 58" from the center of the front u-joint to the center of the rear u-joint Ford OE Part Numbers 4L3Z-4602-KA / 4L344602KA 4L3Z-4602-KB / 4L3Z4602KB 5L3Z-4602-KA / 5L3Z4602KA 5L3Z-4602-KB / 5L3Z4602KB