Outer Limits 4x4 Board

Friends Question!

He Just aquired an 89 sierra,
the previous owner has had the rear diff/axle assembly out,
but I'm not sure how far apart he had it.....

Anyway, problem is that the diff does not turn smoothly by any means - with the wheels off the ground you can hear / feel a clunking noise as you turn a wheel.

Also, when accelerating in 1st and to a lesser extent 2nd, the vehicle shudders.....

What I want to know is are these symptoms consistent with imporperly adjusted backlash in the diff,

or is it more likely that the gears are simply worn/damaged?
And if it is consistent with imporperly adjusted backlash,
will this have damaged the gears over a period of less than 100km?
Cheers

Thanks in advance

sounds like diff has shat itself, spider gears by the sound of it.

mate i'm only 17 but i just replaced the rear diff in mu 86 model lux. wen i drove in all gears the whole car rattled. it felt like the panels were gonna fall off my car! it happened consistently . it wasnt off and on. so me and my mechanic friend pulled it out and found that about 3 teeth were missing from the cron wheel or the pinion wheel( i cant remember). but it was one of those important cogs in the diff centre.
NOTE: try not to clutch start it or do any hill starts with the bad diff in it. you mite just clean off alll the teeth.

im only 17 and i dont know that much about cars. it could just be a backlash adjustment you need to fix. but if the noise is consistent, you'll need a new diff. i got mine from a wreker for $250