Sad, whiny, stressed out, constipated noise when AC is on. Is it dangerous?

Question

Another hot one today...

I noticed in my Ford 5.4 v8 1998 van, when my AC is in the process of workin (like in the time between when it clicks on and clicks off), if I'm driving at certain speeds (most speeds, really) somethin down in there under the hood makes kindof a sad, whiny, stressed out, constipated noise and I can even feel a little vibration in the gas pedal... and you can sorta feel the vehicle slow down a tad like it working harder on sumthin. It don't sound great but its not really gettin no worser. It don't make the noise when just idling and the AC generally works good.

But I got a awful feelin there is somethin going bad in that there AC thang that the drive belt goes acrosst.

If whatever is making that noise finally paid the price and went to heyl, would it be dangerous, or would the AC just stop workin and the wheels keep on turnin good?

Answer 1

I have actually seen an AC compressor on a 5.4 lock up so badly that the engine would no longer start. However, this was after the clutch had gone bad for a long time and the AC was not working at all for a while leading up to this. Also probably not a likely scenario. Most likely, the compressor clutch would stay disengaged if something were to happen to the compressor and the pulley would continue to turn as usual, causing no danger or stress on the engine. I guess the worst that could happen is snapping the serpentine belt if it did manage to lock up, but you would likely experience more severe symptoms before this happened. AC may be on its way out, but most likely not dangerous for the engine or vehicle in general.