Ask Dr. LJ: automotive category

[naiad]

Somehow I made it this far in life without ever hearing of this thing called a timing belt, until now. Fortunately, I learned about it because wotw (of all people) suggested I might need one, not because mine broke. My 2000 Sienna minivan has about 93,400 miles on it. Toyota says I should have replaced the timing belt at 90K. I was planning on driving this van for several to many more years, but had not budgeted for a new timing belt, and spring tuition is due . . . On the other hand, this van will be making a nearly 800 mile round trip in a couple of weeks.

So tell me, auto-wonks, how important is it to replace the timing belt now?