The serpentine belt on your Cadillac is a key part of your engine. It's designed to take the energy from the motor and transfer it to the power steering pump, alternator, air conditioner and water pump, turning those accessories so they can function properly as well. If the belt starts losing tension or breaks, the accessories won't work and you'll be stuck. In this case, the project vehicle is a 2003 Cadillac Escalade, but the process is similar for other vehicles as well.
Locate the belt routing diagram on the core support of the Escalade. This will show you how the factory belt is installed and how the new one will be routed.
Pop the hood and locate the belt tensioner on the engine. It's in the middle of the engine, is round and smooth, and is on a swing arm that pushes down on the belt. There's also a bolt on the middle of it.
Place a socket on the end of the breaker bar and put it on the bolt in the middle of the tensioner. Then pull the tensioner up and away until you see the belt go slack. Once it does, pull the belt off of one of the pulleys and release the tensioner. The belt is now free and can be removed.
Slide the replacement belt around the bottom pulley for the crank, and guide it around the various pulleys and accessories according to the diagram on the core support. A tip: Any smooth pulley is designed to push against the smooth side of the belt, and any grooved pulley rolls against the grooved side of the belt.
Pull the tensioner up again using the breaker bar and socket, then guide the belt to its final position, and release the tensioner. Visually inspect the pulleys to make sure that the belt is sitting squarely on all of them before starting the vehicle for the first time.
