I had the first belt done at 90K, and I have 160K now. Since the truck is 17 years old, (2001 4.7 Tundra), I was thinking of letting it go well beyond 180K. I think it is 1000 bucks to have it done with a water pump etc. The truck has a new frame, and tons of new parts, so it is in excellent condition.
You might want to MAKE SURE your engine isn't an interference engine. My buddy, who is ironically a mechanic, blew up his 2006 or 2007 with the 4.7 when the timing belt broke whilst on the highway. It had right at 90,000 miles and was discussing with his wife he needed to change it the following weekend. When the belt broke, it took out 4 of the pistons along with 5 or 6 valve. I would not wait.
Clyde
