1979-04 Mustang 31 Spline Aluminum Driveshaft Installation Instructions

Improve the acceleration, and reduce vibration of your Mustang by replacing the heavy steel driveshaft with a lightweight aluminum driveshaft from Ford Racing Performance Parts!

Tools Required:

  • 12 point socket, or box end wrench
  • Large screwdriver, and small prybar
  • Jack & jack stands
  • Plastic bag
  • Drain pan
  • Towels
  • Lock Tite is optional

Installation Instructions

  1. Start by lifting the rear end of the car up, and supporting it with jack stands
  2. Locate, and remove the 4 bolts holding the driveshaft to the differential companion flange, with the 12 point socket. To assist in keeping the driveshaft in place while trying to break the bolts loose, insert the large screwdriver, or small prybar through the rear U-joint. Drop the flange end down and pull towards the rear of the car to separate the driveshaft from the transmission. Be careful when removing to no to damage the splines in the transmission.
  3. Wrap a plastic bag tightly around the extension housing of the transmission to prevent any fluid loss. Placing a drain pan under the rear of the transmission will help to keep the work surface clean. Be sure you inspect your new driveshaft for any defects before installing, and check for any leaks around the rear end
  4. Install your new driveshaft by placing in the front of the driveshaft into the transmission extension housing and carefully turning the driveshaft until you've seated the splines inside of the transmission
  5. You might need to turn the rear wheels in order to get the holes to line up between the driveshaft, and the differential flange. Apply a small amount of Lock Tite to the 4 bolts connecting your driveshaft to the differential to keep the bolts from coming loose
  6. Take this time to use the towels to clean up any fluid that may have been lost during installation, or around the rear of the transmission, or differential
  7. Carefully lower your car back down to the ground
There is no break in period required after installation!