Longfield™ Gun Drilled Standard 24-Spline 4340 Chromoly Super Set

Suits: Live axle ToyotaLandcruiser FJ80 HJ80 HZJ80 FZJ8

Includes ABS Tone Ring and Grease cap

The Longfield™ Gun Drilled 30-Spline Birfields are made out of 100% chromoly and are precision polished to remove any imperfections that may cause stress risers. The internals of the birfield are also made from 4340 chromoly and are dual heat treated for superior strength.The birfield has a M8 grease zerk at the end of the stub shaft and is gun drilled through the center of the birfield to allow for grease to pass through the zerk fitting and into the internals. This will save you precious time by eliminating the need to disassemble your axle just to service your birfields.

The Gun Drilled 30-Spline Birfields also have a shallow relief near the splines on the stub shaft known as a Machined Spline Saver. The Machined Spline Saver eliminates stress concentrations caused by grooving from the tool that makes the splines on the stub shaft. The stress concentration from the spline groove is a common failure point on birfield stub shafts.


  • Made out of 100% chromoly and are precision polished to remove any imperfections that may cause stress risers
  • Birfield housing is made out of forged 4340 chromoly steel
  • Birfield stub shaft has dual snap ring grooves to accommodate FJ80s with short and long drive flanges
  • Internals of our Longfield™ birfields are made out of 4340 chromoly steel and then dual heat-treated for superior strength
  • Machined spline saver to eliminate stress concentrations from the spline groove
  • Gun drilled to create grease passage through the birfield
  • M8 grease zerk at the end of stub shaft for easy greasing of the birfield
  • Includes FJ80 ABS Tone Ring
  • Includes extended drive flange dust caps
  • The axle shafts are also made out of 4340 chromoly steel

Optional extra Free wheel Hub Gear Available in Store. #Search 303108 kit# to find


There are specific axle kits that come with our 12 Month Breakage Warranty.Road Runner offroadwarrants that it will repair or replace, free of charge, any eligible axle or birfield that breaks under normal conditions of use and service for 12 months after the purchase of the product. All warranties are limited to the original purchaser and are not transferable to subsequent owners of the product. The warranty period commences on the purchase date of the product. This warranty does not cover any labor costs incurred in diagnosis of defects, removal or reinstallation of a product, nor does it cover any other consequential expenses.


Please note this product is an aftermarket product that is designed to fit the above mentioned vehicle(s), any mention of vehicle brand or model is only to allow you to establish the correct fitment for your vehicle, and is not indicating that the part is manufactured by the original vehicle manufacturer.


SKU 301712-1-kit
Model # 301720-1-kit
Brand Trail Gear
Shipping Weight 17.5000kg
Shipping Width 0.200m
Shipping Height 0.200m
Shipping Length 0.900m