Lexus Repair: timing belt and water pump, timing belt pulleys, gx470 lexus

Question
I have a 2003 gx470 Lexus suv what is the amount of miles I should have on the vehicle before changing the timing belt and water pump? what is considered a good price the work to be done?

Answer
Lexus recommends replacing the timing belt at 90,000 miles.  The water pump is sometimes replaced at this time as preventative maintenance and to save on labor costs.  Its also not a bad idea to do the timing belt pulleys at the same time.  I don't comment on actual pricing but at my dealership the job pays 6.5 hours plus a coolant flush.