* Idler pulley or tensioner failure: These components guide and tension the belt. If they're worn, seized, or misaligned, they put excessive stress on the belt, causing it to fray and break. This is the most common culprit.
* Power steering pump issues: A failing power steering pump can create excessive drag on the belt. Look for leaks or unusual noises from the pump.
* Alternator problems: A seized or failing alternator will also put extra strain on the belt. Listen for unusual noises and check the alternator's output voltage.
* Water pump failure: Similar to the power steering pump, a failing water pump can create significant resistance, leading to belt failure.
* Belt misalignment: The belt might be improperly routed, leading to uneven wear and premature failure.
* Incorrect belt tension: Too tight or too loose a belt can cause problems. Too tight can lead to premature wear, while too loose can cause slippage and eventual breakage.
* Pulley misalignment: If pulleys are bent or not aligned properly, the belt will rub and wear down quickly. This can be caused by impacts or improper installation.
* Accessory drive issues: Problems with any accessory driven by the serpentine belt (like the air conditioning compressor) could lead to increased load and belt failure.
To diagnose the problem, you should have a mechanic inspect your E350's serpentine belt system. They can identify the faulty component causing the excessive wear and tear. Simply replacing the belt repeatedly without addressing the root cause will just lead to the same problem recurring.
