[Y-Blockhead]

Originally Posted by Tom Endy

What I have noticed is that a crack will occur at the inboard end of the locking key. I suspect it is due to the axle nut not being torqued down to 100 ft. lbs. This allows the key to rock fore and aft with acceleration and braking. The crack starts out ever so slight. For this reason I inspect the axle shaft key slots very carefully during a differential overhaul.

Eventually the crack will increase until it travels the full circumference of the shaft, and then separate.

Tom Endy

I wonder how many folks are out checking the torque on their axles this morning...

I actually did check mine ~2 weeks ago while doing my "bolt check" routine.