1301-232 – Companion Flanges – 990″ Splines Dia – 1.495″ Hub Dia – 3.386″ Bolt Circle Dia

The 1301-232 companion flange is machined for direct spline engagement on the differential or transfer case pinion shaft. The 3.386 bolt circle and 6-bolt pattern align precisely with the mating driveshaft flange yoke, establishing the correct phasing relationship for balanced, vibration-free driveshaft operation.

Dimensional Specifications

Pinion Preload and Companion Flange Replacement

Replacing a companion flange is an opportunity to restore pinion preload to specification. If the flange was loose or worn oversize on the splines, the resulting micro-movement will have fatigued the pinion nut's bearing surface and potentially allowed the preload to drop. Before installing the 1301-232, measure existing pinion rotating torque and compare to the service specification. If preload is low, replace the crush sleeve and set new preload.

The 23-spline engagement of the 1301-232 provides the same torque capacity as the original equipment component. Spline tooth contact should be checked by applying a thin coat of Prussian blue before full assembly -- uniform contact across all teeth confirms correct fit.

Flange Bolt Pattern and Driveshaft Phasing

• Match-mark the driveshaft and companion flange before disassembly to preserve factory phase
• The 3.386 bolt circle on the 1301-232 must be confirmed against the mating flange yoke before bolting up
• Use new, grade-matched fasteners -- reusing old bolts risks fatigue failure at the pinion flange joint
• Torque to specification in a cross-pattern for even clamping force

Available for Immediate Shipment

Universal Driveshafts maintains stock of the 1301-232 companion flange for same-day shipment. Our technical team can cross-reference OEM part numbers and confirm dimensional compatibility for your application before you order.