bergie33
+1y
Here is how I have tested clutches in the past...
Get the truck up to operating temp, then twist a piece of newspaper together, so that it is long and stiff, then stick it in the fan. If the paper stops the fan, then the clutch is bad. If the fan shreds the paper, then the clutch is fine.
My experience, don't buy the Kragen/Pepboys $50 fan clutch. Splurge for the $125 OEM fan clutch. I bought the cheapo, and the clutch is engaged about 70% of the time, and it sounds like I am driving down the road with a V8. That's even in Utah, when it is 10 degrees outside.