02 1.8 Auxillary/fan belts - Focus1.8TDCi
I'm not sure what the name is, but its the belt that drives the power steering, alternator etc. The haynes manual said its an easy job, has an automatic tensioner and should be changed every year. The current belt has done over 40k. I'm quite a diy person myself but it looks very awkward to change.

It looks "OK" from the bonnet and there are no visual or audible signs its about to go. What should I do? Wait till there's evidence of a problem or change it now? Is it a diy job? I don't hear of any major problems when it snaps but surely it would make the car undriveable if it does?