We're going on vacation in two weeks (eek!), probably driving 1500 miles or so, and our 1996 850 has just hit 140,000 miles. We bought it used, so I don't know exactly when the timing belt was replaced, though the car had been maintained well, leading me to think that regularly scheduled maintenance happened.

So, we should be replacing the belt; but time is limited, and I'm wondering what kind of tolerance these motors have. Can I safely get away with belt replacement at, say, 72,000 miles, or should I be out there this weekend?

Part of the problem is that belts are way more expensive at the local parts houses than online, but saving $50 and risking $3,000 for a new motor is false economy, if the belts really like prompt replacement.