Multi vee belts - bmw 320d - former farmer
My 320d is approaching the 100k mark fairly soon and has had the coolant and brake fluid changed and it just struck me that the fan belt might be getting tired by now.

I was wondering what life expectancy would you get from these?
Multi vee belts - Roger Jones
Does the Car-by-Car Breakdown give you any clues? In any event, 100k sounds like more than a good age for a fan belt, whatever the car. Unless anyone knows better (quite likely), I'd get it changed right away.
Multi vee belts - elekie&a/c doctor
Polyvee belts rarely snap or break ,but check the ribbing for multi cracking or sections missing, or frayed edges .These belts will do well over 100k without any problems.
Multi vee belts - bmw 320d - MW
I might replace them, and make the old ones the spare. No point having a good one in the boot, and a poor one on the engine.
Multi vee belts - bmw 320d - Roberson
Its always better to be safe than sorry. I don't know what kind of work the belt has to do on this particular car (no doubt alternator, AC pump and power steering pump) but the condition of the belt on my Polo at similar mileages was very poor indeed, and all it did was drive an alternator.

www.honestjohn.co.uk/forum/post/index.htm?t=37213&...f
Multi vee belts - bmw 320d - Hamsafar
I'd do it, as if it goes, you can guarantee it will be at the least convenient time and place and noone will have the correct belt at the time etc...

Don't let failure dictate your replacement and maintenance schedule.