10 bolt Front Problem 1990 Sub V2500

[Bright Idea]

I have a 1990 V2500 Suburban. It has the 10 bolt GM front axle and I am led to believe that it would have the 30 spline inner shaft ? Is this correct ? It is 4:10 gear Ratio. I have a random intermittent popping sound/clunk when running in 4wd. I believe I have narrowed it down to the right ( passenger side ) It only does this in 4wd with both manual hubs locked. with the right hub unlocked and the transfer case in gear either 4hi or 4lo the noise /popping does not happen. I have had the manual hub apart and it is fine and works as it should. I suspect either something with the axle shaft or internal in the differential. This clunk/bang occurs very randomly and does not involve turning. Any Ideas before I tear into it ?

 

[dvdswan]

Steering knuckle u-joint?

 

[Bright Idea]

I am not real familiar with 2 piece axle u joint failure.With the limited access it is hard to tell if there is any slop in the joint. Possibly this is the beginning of the u joint failing ? Turning does not seem to make any difference ?

 

[TubeTruck]

Go from behind the front axle and grab the drive shaft an twist it back and forth. See if there is any play in the u-joint. You can also use a big screwdriver or prybar to see if there is any play.

You should see this

You must be registered for see images attach