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Spicer · Drivetrain
4-40-721
In stock · ships from Knoxville
This is a weld-in splined stub shaft (also called a tube shaft) used to build or repair a heavy-duty driveshaft.
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Universal fit
Universal component weld-in stub shaft. Used in custom or replacement driveshaft assemblies for various heavy-duty trucks and equipment. Requires professional welding and balancing.
Part data verified against 4 catalog sources
Numbers this part supersedes or interchanges with. Showing 4 of 4.
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It provides the male spline that slides into a slip yoke or companion flange, allowing the driveshaft to change length as the suspension moves. You typically replace it when the splines are worn, twisted, or damaged, or when building a custom-length driveshaft for a truck or heavy equipment application that uses 3.5-inch diameter tubing with a 0.095-inch wall thickness.
Part Number: 4-40-721
9.219 X 1 3/4 X 16 TUBE SHAFT
Category: Driveline
Unit: ea
Dealer: Post Onsite
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