4340 Chromoly Axle and Birfield Kit The new 30 spline axle kit is a perfect match for your next budget build. This kit offers an increase in strength over stock axles without breaking the bank. This kit comes with a 12-month warranty against breakage and the 30 spline birfields are single heat treated. With larger tires and more horsepower being used on the trails these days, upgrades to your axle are more critical than ever.

In a Toyota, one of the common failures is the stock 27-spline birfields and axles. The solution to this problem is our Longfield 30-Spline 4340 Chromoly Axle and Birfield Kit. These birfields and axles will get you to wherever you need to go and give you confidence and peace of mind to run any trail.

The Longfield birfields are made out of 100.0 Percent chromoly and are precision polished to remove any imperfections that may cause stress risers. The Longfield birfield housing is made out of forged 4340 chromoly steel. The axle shafts are also made out of 4340 chromoly steel. The internals of our Longfield birfields are made out of 4340 chromoly steel and heat-treated for superior strength.

The Longfield 30-spline Birfields allow up to 40.0 degrees of turning radius and have a consistent breaking point of 8900-9000 foot-pounds of torque All testing data is based on internal testing at TGI. 76.0 Percent Stronger than stock axles.


P/N Description Short Side Long Side
301688-1-KIT Longfield 30-Spline Super Set 15-7/16″ 31-7/16″
301724-1-KIT Longfield 30-Spline Super Set, +3 18-7/16″ 31-7/16″
301725-1-KIT Longfield 30-Spline Super Set, +5 19-7/16″ 32-7/16″

Additional information

Weight 38 lbs
Dimensions 36 × 7 × 7 in

Pickup/4Runner, Pickup/4Runner +3, PR5