I've been hearing a slight groaning sound from my power steering pump when in parking lots at slow speeds...I've checked the fluid which seems to be fine and cant see any leaks...is this an early warning sign that I'm about to lose the pump?...has anyone else had similar issues?...or is it maybe just because of the heat and load with the A/C on? (its been pretty hot here of late)...if the pump is getting ready to let go I wanna be ready since it looks like its gonna be a real bear to change.