Why Does the Car Belt Squeak?
3 Answers
The reasons for a car belt squeaking are as follows: Belt wear and aging: Whether it's a V-belt or a multi-rib belt, wear and aging are common during use. Incorrect belt model: The belt on the engine is always under tension, and over time, due to different belt materials, it may stretch to varying degrees. Oil leakage: Oil leakage from the engine or power steering pump can cause the belt to slip due to oil contamination. Tensioner damage: Damage to the automatic tensioner or manual fixed tensioner can prevent the belt from maintaining the necessary tension for proper operation.
I've been driving for over twenty years and have seen plenty of cases of squeaky belts. The most common issue is a loose belt. Try pressing down on the middle part of the belt with your hand—if it gives more than half a centimeter, it likely needs tension adjustment. Another possibility is that the belt has aged, showing cracks or wear, especially in older cars with over 70,000–80,000 kilometers. The noise tends to get worse with temperature changes. Once in winter, my car's belt squealed, and I found it was contaminated with oil or dust—a simple cleaning fixed it. But don’t underestimate the sound. If it persists, the belt could suddenly snap, causing the alternator to stop working, the battery to stop charging, or even the water pump to fail, leading to engine overheating and a breakdown. So, my advice is to get it checked by a professional as soon as you hear the noise—don’t try to fix it yourself. During routine maintenance, have a technician inspect the belt’s condition and replace it if needed to avoid trouble on the road.
I've been learning to tinker with car repairs lately and found that belt squeaking usually has a few causes. It could be insufficient belt tension—just use a tool to check the tightness to diagnose. Or, the pulley might be worn or misaligned, causing uneven friction and noise. Humid weather can also trigger this, as moisture makes belts slip and squeak louder. From personal experience, when my car's belt squeaked, spraying belt lubricant temporarily fixed it. But if it keeps squeaking, beware of belt aging and snapping risks, which could affect power steering or AC function. I recommend regularly inspecting the belt surface for cracks—routine checks can prevent major issues.
