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redrilling axle stud holes question

Thwak

Jr. Member
Joined
Oct 24, 2007
Messages
129
Loc.
Clear Lake, TEXAS
I have 35 spline full width rear axle shafts. i did the BCB rear disk conversion and apparantly didnt get the wheel studs seated all the way because the wheel studs backed out and the tire fell off. To get back to camp had to bolt the wheel on which buggered up the wheel and axle shaft stud holes. Got wheel fixed with steel inserts no problem.

Question is can i clock the axle and drill new stud holes in the void between the original holes? How hard is that to do or should i take it to a machine shop for precision indexing 5 on 5.5 bolt pattern? Also what size pilot hole do i drill for the new studs to be pressed into?

Thanks in advance.
 

Apogee

Contributor
Bronco Guru
Joined
Nov 26, 2005
Messages
6,097
My opinion is that you should have it done professionally by a machine shop or replace the axle. When I design hubs or anything with a wheel pattern, I'm usually shooting for an absolute position within .001" to .002" of true position since there will be a tolerance associated with the wheel as well. Any variation between the wheel pattern of the wheel studs and the 60 degree conical seats ultimately results in bending of the wheel studs due to misalignment...a little is fine...more than that can lead to serious problems that can result in death or injury to you or those around you.

The pilot hole size should not be drilled, but rather reamed so that you can hit your dimension and tolerance. A drill typically cuts large by .003" to .008" and sometimes larger, depending on several factors. The size of the hole should be determined by the knurl diameter of the wheel stud and the material of the axle (1541H?), however .005" to .008" interference is typically appropriate in steel in my experience.
 
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