The timing belt kit for a Toyota wears over time and must be replaced following the constructor's instructions. If you do not replace your timing belt when necessary, it can snap thereby causing irreversible damage to your engine.
The timing belt is the car part that sychronizes the movement of the engine's pistons and valves. To ensure this process works properly it is best to not only replace the belt but the tensioner pulley and the water pump as well. The tensioner pulley ensures the timing belt keeps the right tension and doesn't slack. A timing belt kit consists of the belt and the tensioner pulleys. Some kits also contain the water pump. Whether one or more tensioner pulleys are needed, depends on the model of your Toyota.
To ensure you buy the right timing belt kit, please select your Toyota's model and engine type into the search engine.