It's really up to you, if you want to spend the money and have peace of mind then just go for it man. There are guys on this board that have pumps with over 90k on them and they will just change them when they see failure signs. If thats in the back of your mind so much and you want to replace it just do it. That's my opinion.
Check this out, my mechanic told me last week not to worry till i see signs... like you I have concerns about my 2000 Z3 2.3 but he said relax and don't stress. My car has little over 35k on it so I figure I'm good for a very long time but i will surely keep an eye out for signs of failure.
Last edited by wired; 05-01-2010 at 07:24 AM.