Good afternoon group. I am looking for information and or opinion dealing with ring and pinions. This question can be applied to any and all ring and pinions. My specific case is with the above listed truck. The basic question is how tight should the pinion spline to yoke interface be. I am looking at the quality of finished machine work and the problem we all face with reverse engineered products from other countries. I am interested in the degree angle of the splines and the depth the splines are cut. The problem that I ran into, I am rebuilding the rear diff in the above listed truck. It has a 10.25 Ford gear in a Sterling diff housing. It is the later model with the long pinion. I purchased a Yukon ring and pinion as a replacement. The original yoke and a brand new Ford yoke would not engage on the new pinion. Once placed on the pinion it would only engage about an inch. I spoke with the supplier of the Yukon gear and their tech department stated ( and their commercial available gear installation book ) that you just have to drive the yoke onto the pinion with a dead blow hammer. The old yoke and the new Ford yoke go on the old damaged pinion with no problem but will not go on the new pinion. If I were to drive the yoke onto the pinion as instructed I do not see how I would achieve and accurate crush on the crush sleeve or Inch pound preload on the pinion assembly. I am not going to do this I have opted to send this ring and pinion back and have found a domestic made unit, I am interested in any opinions on this situation because I have not be able to find much tech information. Thanks for your opinions

James Sessoms
Technician/Manager
Sessoms Automotive
Suffolk, Virginia, USA