The garage where I have my car serviced 2X a year (oil change, minor tune-up at 7K miles) says the water pump is starting to leak. I haven’t noticed anything, but the mechanics suggest a $600 repair. First, is this a common problem with my model car? Second, is the estimated fee appropriate? Is the car or am I in any immediate danger (how long can I put this off)? I’ve only been going to this garage for a couple years as my previous CarTalk-referred mechanic retired. I’m not sure whether to trust the new guys (no longer a single individual, but a group of mechanics in a middle class residential suburban neighborhood).