braverichard, I think that mechanic is full of rubbish and he's simply trying to make money. The proper way to go is to check the chain for stretch and inspect the guides and tensioner. Every car will wear its chain at a different rate, and to say that every car needs a timing chain replacement every 100K miles is BS. I know LarryBible went 300K+ miles on one chain and it still had very little stretch at that time. Of course chains do occasionally break, but it's usually caused by something jamming the chain, not by the chain itself. That's why replacing the chain without paying attention to the guides and tensioner is useless.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL