I would guess the timing belt would last another 20k miles or so. The problem is that you would be worrying about it every time you drove your car because if it breaks, your engine will need major repairs. I changed mine at home at 70k because I wanted the peace of mind. Volvospeed.com has great directions. The job took most of the day since it was my first time but it is not a complicated job. One thing I will pass along if you try the job at home, is it was difficult for me to see the "mark" they were talking about on the lower pulley. You need a bright light and a mirror. Good luck.