Because serpentine belts use a spring loaded tensioner for adjustment, belt replacement tends to be somewhat easier than it used to be on engines where accessories were pivoted and bolted in place for tension adjustment. Basically, all belt replacement involves is to pivot the tensioner to loosen the belt, then slide the belt off of the pulleys. The two most important points are to pay CLOSE attention to the proper belt routing (since serpentine belts tend to be "snaked'' all different ways through the pulleys) and to be sure the V-ribs are properly seated in all the pulleys.
Although belt routing diagrams have been included in this section, the first places you should check for proper belt routing are the labels in your engine compartment. These should include a belt routing diagram which may reflect changes made during a production run.
NOTE: Take a good look at the installed belt and make a note of the routing. Before removing the belt, be sure the routing matches that of the belt routing label or one of the diagrams in this book. If for some reason a diagram does not match (you may not have the original engine or it may have been modified), carefully note the changes on a piece of paper.
Fig. 1: Often the underhood label will display the serpentine drive belt routing
Fig. 2: Relieve the belt tension by pivoting the automatic tensioner away from the belt, then remove the belt
Fig. 3: Verifying serpentine belt alignment in the pulley
Fig. 9: Serpentine drive belt routing — GM 3.1L engine L/N bodies