Few months ago they disabled the AC and now serp belt shredded again! now they say replace compressor and hook up AC- what??? and $2000

Have AC drained, remove serp belt, jack up car and remove lower front access panels, unplug wiring , remove 13or 15mm bolt from manifold lines on back of compressor,remove the 4 mounting bolts.

Depends on what kind of noise and where its coming from.
Could be a problem inside the compressor, or the ac clutch, or something else.
Did you get a warranty with the compressor ?

Yes that is very likely it. Since you changed the belt, you should know - Is it the tensioner pulley ? Otherwise it is probably the water pump. The problem is the bearings.. If the bearings are locking up, the resistance will shred the belt quickly.. the part needs to be replaced is the bearings. Waterpump bearings are built in to pump. Change whole thing. (may need to transfer the pulley)

if the ac compressor won't turn even with the engine off,it's not the compressor but the freewheel bearing inside the pulley,
even if the compressor is bad ,changing the bearing will allow the serp belt to turn the pulley.
I'd just change the bearing .

yes

take the belt off and carefully check to see if any of the pulleys are out of line and check to make sure they spin smooth and true check for bearing wear and noise in any of the pulleys cause it sounds like simply there is a pulley out of line

is the a/c working ok??? shredding the belt may be cause by the a/c compressor problems. the "chunk" maybe not, but shredding tells me something does not spin when it should. I dont know why the mehanic put a new pump on that had a problem with the pulley, it should be smooth. anyhting that the belt runs should be smooth and east to turn, make sure that all of the grooves are clean, no remnants of the old belt.

Did you replace the belt? You mentioned the pulleys, but not the belt. If the belt is new, check the grooves on the pulley that appears to be a problem and make sure there is no residue stuck in the grooves. Also, make sure you can't wiggle the pulley that is giving the problem. It is possible for a belt to cause some damage when it comes apart.

never seen a truck like this ,iam in spain but from the sound of it one belt drives a/c and another the power steering and altenator ,pos water pump as well but this could be driven by the timing belt .As i said i have never seen one of these trucks .If i had it in front of me i could soon tell you .

You can buy an A/C bypass pulley from an O'reilly auto or anyone that supplies Dorman parts. the pulleys are cheap and allow you to mount things and use the stock serp belt. You will have no AC ,though. The kit is designed with the intent of eliminaing the compressor, which is very expensive to replace.