After reading John's comments, I think my advice works in your case only because it is a Mercedes. It might also apply for a Jeep or Volvo 240D.
We're talking about a 16 year old car. If this were the average American or Japanese car, another 8 years of driving is not likely possible. Or rather, the car wouldn't be worth limping along for another 8 years.
But the build quality of a Volvo 240D or Mercedes is such that after 16 years they are still robust and solid. Another 8 years is not out of the question.
However, if you had a 16 year old Chevy Cavalier, we wouldn't be having this conversation....
Now, Let me get back to American Idol and then I have to put my twin babies to bed.