thermostatic fan clutch engaged all the time
 

I have a 92' Ford Ranger XLT with 2.9 V6. My mechanic says my thermostatic fan clutch should be replaced. He got an abnormal "high side" reading on his electronic A/C gauge. I am not so sure I agree . It has no silicone fluid leakage, no fan wobbling, and no overheating.

But one thing that I have noticed is that this clutch seems to be engaged 100% of the time engine is running. I see no variation in fan speed sound at all. Does it need replacing?

Thanks,
Dave