Squealing Sounds - What Does It Mean?
Cars make a lot of sounds. Squealing is a common one reported to mechanics. How do you tell how much to worry when you start getting squeals out of your car? That depends on a number of factors. Knowing just a few of these can help you narrow down the problem. Even if you can’t fix it yourself, you can talk intelligently with your mechanic and maybe save some money by avoiding unnecessary repair.
Squealing sounds - a sustained “eeeeeeeek” - are usually a belt of some sort losing grip. If a squeal comes from the front of the car you can lay good odds that you either have a loose belt, or a worn belt. If you haven’t changed your belts in more than three years, or you can’t remember when you changed them, better plan on getting it done. If the car has had belts replaced within the last several thousand miles, they will likely just need tightening.
When the squealing happens can tell you something too. If it happens when you accelerate, it is likely to be your alternator belt in need of adjustment or replacement. If it happens when you turn on the air conditioner, it’ll be that belt.
Older cars have several belts, newer ones have a single belt called a “serpentine” belt. If the serpentine belt fails, your whole care will stop running. Serpentine belts have a device called a tensioner which keeps even pressure on the belt. If you have had your belt serviced in the not-too-distant past, you or your mechanic should check to make sure the tensioner is either tight enough, or is still functioning properly. It may need replacement.
Squealing that sounds like dragging metal across metal coming from the front or rear could be brake issues. Disc brake pads have a thin piece of tin called a telltale that will start to drag on the rotor when the pads wear down. This makes a terrible squall when you drive. You can all but confirm this diagnosis if the noise changes as you apply brakes as you drive. Rear drum brakes lack this device, but a broken spring or other item inside the drum will make a similar metallic squeal. In my experience you could wait until payday or so for front brake squealing, but rear brake squealing you should tend to as soon as you can.