The air works fine for 15-20 minutes then it stops blowing cold. Looked at the compressor and it was turning but very slow and jerkey, more like a second hand on a clock. What would cause this?

2005 ram, cummins

not sure why my signature does not come thru when using phone.

 

Telling the members what year, type and model of vehicle may help in the diagnosis.

 

Can you just replace the clutch on the air conditioner?