As just described.When I turn the AC off it goes away completely.

Any ideas?

When mine groaned it was low on fluid. Actually the level looked OK but when I added a little fluid it fixed it. Considering the AC effect, it might also be the belt I suppose.

Mike

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

I just drained and refilled the resevior a little over the hot full mark like it came from the factory.Seems to have quieted a bit.

The groans seems to be more the tires than the ac compressor or PS pump since at very very low speeds.It's just more pronounced with the AC on.