3500 stop in rev and neutral

[Lensing]

Hello, newbie here.
Have an interesting situation. When I shift to reverse whether using accel or not truck rolls one tire rotation and stops hard, with a bang, rather like parking pin relanded except you can accel through it but eng loads good. It is 99% repeatable and can replicate in neutral. Forward no probs. Brand new prob. 6.7 4WD Dually, approx 157K, 2010.
Any insight?

 

[Lensing]

Hello, newbie here.
Have an interesting situation. When I shift to reverse whether using accel or not truck rolls one tire rotation and stops hard, with a bang, rather like parking pin relanded except you can accel through it but eng loads good. It is 99% repeatable and can replicate in neutral. Forward no probs. Brand new prob. 6.7 4WD Dually, approx 157K, 2010.
Any insight?

So got rear axle up, not running in park, rev, neutral can roll wheels forever. Running in rev with wheels off ground, rolls freely. Fluid level good and clean. Back on ground issue is gone. Surely is not fixed. Guessing time to drop pan change filter and oil. Anybody have any ideas on this?

 

[cerberusiam]

If this is a 68RFE check the spin on filter base in the pan to make sure filter is tight and the base is not cracked.

 

[Tuesdak]

Check the oil in the diffs as well. Offhand sounds like you broke a gear tooth or are forcing debris through the gears or a bearing.