I know it's a notorious problem on Fords that the PS pumps scream, but I've never heard of them groan. Mine barks and groans whenever it's cold outside when you move the wheel. Basically, whats the deal? My Bronco's pump screamed a bit, my girlfriends Explorers screamed A LOT (still does), but I've never heard of one that groans. This anything I should be worried about, or is it just a standard problem?