Could anyone give me any information on what could be wrong with my A/C when the clutch disengages and the fan turns off? I checked the pressure on the low side (55 psi). I thought initially that the system needed recharging before I ran across the high pressure in the low side. The clutch doesn't free spin when disengaged. Could it be the TXV?

The clutch won't spin easily, as you'd be turning over the compressor with it. Was 55 psi low side with the compressor running? If so, you've got blockage. If not, and the system was at rest, there's just not much charge in there.

What's a TXV? Expansion valve? It's possible. I deal more with domestics, and orifice tubes and clogged receiver/dryers are common places for blockage.