Spindle end replacement is a common procedure JASPER performs on full-floating differentials. The spindle ends of a differential take lots of abuse in the field, and sometimes, they’re not well taken care of. “They bear the weight of that vehicle, and we see many different failures come from the cores that we get,” says JASPER Differential Division Manager Thom Ireland. “It can vary from damaged threads to bent spindle ends. We’ll have bearings that have spun out, and even some spindle ends completely blown apart.” One repair JASPER never does is butt-weld a spindle end onto the end of an axle tube. “The weight of that vehicle is out on that spindle end, so you’re potentially going to have tire wear issues, and you could, in fact, have catastrophic failure if that weld failed and broke off of the housing,” Thom said. “We never recommend that repair and would certainly never do that to our unit.” The JASPER method of spindle end replacement involves removing the spindle end on a lathe to the point where it meets the housing.  The axle tube is bored out with several passes on the lathe in preparation to accept the new spindle end. “Once it’s bored out, the axle tube is heated until it’s glowing red hot,” said Thom. “A new spindle end, made in-house by Indiana Tool & Die, is inserted to the desired specified length.” The housing is then cooled, providing a press fit of the spindle end to the axle tube. Finally, a submerged arc welder is used where the spindle meets the axle tube, ensuring a perfect fit that will last the unit’s life. Click the image above to watch how the process is done. You can also call 800.827.7455 or log visit www.jasperengines.com to learn more about the remanufactured differentials of Jasper Engines & Transmissions.