Toyota Repair: timing belt replacement interval


Question
I have a 2005 4 cylinder Camry with only 20K miles on it. It's used for running errands in a semi-rural area. Trips from 10-50 miles and no sitting in traffic so there should be little engine wear. If you only consider age it's overdue for a timing belt renewal but not even close judging by mileage. Do the belts fail because of age or is it more wear? I get the feeling that I'll be doing unnecessary, expensive maintenance replacing it now. With your experience what would you guess the belt looks like at this time?

The car has had no fluid changes other than oil. Do you advise any fluids to be replaced at this time? Are specific OEM products from the dealer required?

Answer
hello, the 2005 camry uses a timing chain which should last the life of the engine, it uses a single serpentine drive belt to drive the water pump, alternator, power steering and air conditioner, inspect this belt for cracks due to age, they normally last about 100,00 miles.
At mileage other than replacing the oil and filter, air filter and cabin air filter there is not much else to do.
Spark plugs @ 90,000 miles
trans fluid @ about 60,000 miles
rotate the tires for even wear at about 5,000 mile intervals and check the brakes