<VV> Late axle retaining bolt

[NicolCS at aol.com]

This has been hashed around many times.  The spec in the shop manual is 
incorrect for the 
differential yoke bolts.  Here are the entries in the Rear Axle and 
Suspension torque section:

Drive spindle flange: 100 to 125 ft-lb.  In GM-speak, a flange is the type of 
u-joint yoke with a hole in the middle.  This would be the outboard side for 
the rear wheel bearing and drive axle flange nut.

Drive spindle yoke nut: 100 ft-lb.  In GM speak, a yoke is the type of 
u-joint yoke with a shaft in the middle.  This would be the inboard side and THIS IS 
THE SPEC THAT'S IN ERROR.  I can tell you from personal experience, the bolt 
will break far short of this value.  30 ft-lb is more like it.

Axle shaft retaining bolts: 15 ft-lb.  These would be the drive shaft u-joint 
straps - as it says it retains the "axle" - it does not say "yoke" and this 
spec seems about right.


One theory is that the 100 to 125 ft-lb spec. (125 in '66 up suppliments) was 
supposed to have been INCH-POUNDS.  That maxes out at 12 ft-lb and the 
experts feel this is kinda low.

Looking up the "generic" torque value for a 3/8"-16 grade 5 bolt "yields" a 
33 ft-lb specification as the 75% of yield stregth number. Taking that down a 
little we've concluded in the past that 25-30 ft-lbs is about right for this 
fastener.

Any thoughts???
Craig Nicol