Upgrade your rear axle assembly with the ultimate solution for strength, precision, and versatility. Crane Axle’s 14 Bolt 40 Spline Spindles are engineered to handle the punishing torque of rock racing and the heavy loads of hardcore trail riding.

Each spindle is machined in-house from 4140 chromoly steel slugs, heat-treated for maximum hardness, and finish-ground for perfect bearing accuracy. By accommodating a massive 40-spline axle shaft and a thicker spindle wall, this setup drastically improves yield strength (up to 80,000 lbs vs. 20,000 lbs for stock), eliminating the risk of bending or twisting under stress.

Universal Fitment for Custom Fabrication We engineered these spindles for maximum adaptability in custom builds.

Heavy Duty Base: Features a longer, larger OD backside for a secure, high-surface-area weld.
Custom Bore Compatibility: While robust enough for heavy wall tubing, the spindle end is fully machinable. It can be turned down to fit inside axle tubes with a bore as small as 2 inches, giving you the freedom to utilize a wide variety of housing thicknesses without sacrificing the strength of a 40-spline setup.

Build with confidence. Build with Crane.

Includes:

(2) 4140 40 Spline Spindles
(4) 40 Spline Spindle Nuts
(2) Spindle Nut Retaining Dowels

Optional Socket sold Separately

Notes:

Must modify wheel hubs internally
Spindles come standard with 3" OD (can be machined down to fit inside axle tubes as small as a 2" Bore )
100% Made in the USA

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Axle Specifications

Components & Upgrades

custom axles
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