How do you know you have a bad fan clutch? And could a coolant temp sensor be a cause of the fan to come on when acceleration with a cold, no load truck?
Many times these will set a DTC in the PCM. Symptoms may be delayed engagement, delayed disengagement, over heating, or fan stuck on. There are many different inputs to the PCM to control this fan clutch including: engine coolant temp, oil temp and, transmission temp. You should monitor these inputs along with the PCM control signal to the fan clutch before condemning the clutch itself.