Question: My car repair shop said I need a new serpentine belt, but I don’t see any cracks in it. Does it really need to be replaced?
Express Car Care Answer: I appreciate your concern. Old style neoprene belts would crack with age, making it pretty obvious to drivers when they needed to be replaced. Nowadays, serpentine belts are made from different material that doesn’t crack or glaze the way neoprene did.
Just to explain, the serpentine belt transfers power from the engine to various accessories, such as the alternator, power steering pump and air conditioning compressor – even the power brakes and water pump on some vehicles. Modern serpentine belts have several grooves running their length. These grooves mate with the pulleys on the accessories. When the belt is within its useful life, it spins the accessories at the designed speed.
Over time, belt material is worn away. When as little as 5% of the material is lost, the belt can slip and won’t spin the accessories properly, leading to stress and damage.
Using a special tool, your knowledgeable service adviser can measure the material lost in your serpentine belt. He will indicate if it needs to be replaced.
It’s important for drivers to understand that the serpentine belt is part of the accessory belt drive system, which also includes the serpentine belt tensioner and any idler pulleys. The belt tensioner has the same service life as the belt itself, so if it is time to replace the belt, you should also replace the tensioner and idler pulleys as well.
A worn belt tensioner can cause the belt to slip and not do the job it’s suppose to do. Running too long with a worn belt, tensioner or idler pulleys causes excessive heat at the accessory pulleys, resulting in inefficiency, damage and premature replacement.
Express Car Care can perform tests to see if your serpentine belt is worn and should be replaced. Ask your service adviser if it’s time for a serpentine belt system replacement