At what mileage should I replace timing belt

your car has a timing chain - not a belt. check your owners manual for replacement interval.

timing belts and chains usally dont need to be changed, unless you are having trouble with the timing jumping, or it flat out breaks. if your car has hesitation that can not be trouble shooted it might be a loose timing chain or belt, odds are the timing chain or belt is fine, espeically in a 2000 car,, I have a 94 camaro, with over 230,000 miles on it, and my timing chain is fine.. also it depends on how you drive your car as well,, if you beat it hard, then change intervals will be alot more than just driving it normaly