Clunking sound. Not sure what to check next

[cj5walt]

Working on 87 a jeep comanche 5"lift auto np231 dana44 rear

I have a clunking/knocking sound that starts at 10 MPH and increases frequency as speed increases. If I remove driveshaft sound stops. Driveshaft has new joints. Axle has new wheel bearings checked carrier and pinion bearings they are OK as well. If the truck is on lift engine running in gear tires turning it does not make the sound

I'm not sure where to go from here. Its beginning to drive me crazy. Any help paint s greatly appreciated

 

[Stuntman Autoworks]

Do you have an sye? If not maybe the driveshaft is too short and almost falling off of the output shaft. My xj used to make a kind of knocking/grinding noise before I put the sye on.

 

[cj5walt]

No SYE. Drive line length is correct. Double checked when had new shaft built a couple months ago

 

[cj5walt]

Driving home last night heard a loud bang. Like the floor was smacked with a hammer and clunking got worse now has a pop every so often. Thinking may be in t-case. Will tear down next week to see