Long and Short 31 Spline Cut-to-Fit with Bearing Kit, Fits Ford 9" Inch

These steel axle shafts have a natural finish and are sold as a pair. They are perfect for small shops and will allow you to build your own custom width rear end easily. Axle length is measured from the flange to the end of the splines.

• Circle track / off road application 5/8" thread wheel studs sold separately and
• Street application 1/2" thread wheel studs sold separately and
• 9 Inch Ford
• 31 spline axles
• Long & Short axles included
• Axle has the new style big bearing ends on it
• Bearing measures 3.150"
• Bearings already pressed in
• 2-1/2" Offset
• Drilled for 5 on 4-1/2", 5 on 4-3/4", and 5 on 5" wheel bolt patterns using 0.685" knurl dia.
• PA20 set bearing
• AR375 Torino retainer
• Axle length is from the flange to the end of the splines
• Axles have 3 bolt patterns in them: 5 on 4-1/2", 5 on 4-3/4", and 5 on 5"
• The hub pilot (center of the axle flange) measures 3.055"
• The O.D. of the axle flange measures 5.93"

For more information on determining the proper axle length and the Ford 9 Inch, be sure to check out our tech articles; and .

Long:

• 33" length with 9-1/4" of spline

Short:

• 29.51" length with 10" of spline

Installation Notes:

Disc brake kits may require increasing the i/d of the center hole in the rotor to match the o/d register or hub pilot on the axle flange, or reducing the diameter of the register or hub pilot on the axle to fit properly to the i/d of the rotor.

When installing new axles in rearends with posi traction differentials, be sure to install the driver's side axle first to keep the splines properly aligned. Failure to do so may move the two splined gears out of alignment, and it may be difficult to install the driver's side axle properly if the passenger side axle is already installed.

If installation of passenger side axle is done first it may require two people when installing the driver's side axle, with both parties rotating reach axle until splines are in line and the driver's side axle fully sides into the housing.

When cutting axles to desired lengths, it is recommended that the following procedures are performed:

• Normal steel cutting machinery (cold saw, band saw, chop saw, etc.)
• Using a sleeve around the axle such as a small piece of PVC tubing - this allows:
  • The axle to be spun in place while being cut
  • A perimeter cut around the outer diameter assisting in keeping the cut square
  • Avoiding the build-up of too much heat by doing a straight cut (like a knife though a stick of butter)

To ensure you get the most out of your new 9 Inch components, it is recommended that you perform a proper break-in process:

• Use a name brand mineral-based gear oil, preferably 85w140 (Extremely high quality synthetic oils may be used once break-in process has been successfully performed)
• Place vehicle on jack stands and let the rearend spin while the vehicle idles - run transmission in both forward and reverse periodically throughout the process
• Continue to run the rearend until the pinion gets hot (place hand on bottom of the differential housing to verify this)
• Proper break-in allows:
  • The ability to install new axles and hit the track the same day without worry
  • Extended life for rearend components
  • Keeps the quality and life of your gear oil