Car noises squeaks and rattles

Car noises such as squeaks and rattles are at the top of the complaint lists from consumers that purchase new automobiles. Working as a line technician at a dealership for 20 years much of my time was spent hunting down these annoying sounds.

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Car noise help button


In the 80s and 90s sub frame vehicle construction was not as solid as they are today. Squeaks and rattles are complained about less today then just a few years ago.

As a mechanic or even a vehicle owner trying to hunt down one of these annoying sounds directional hearing skills will be your most effective weapon.

This page will discuss types of sounds that your car will make and help to dissect the noises to send you in the right direction to solve the problem. I would like to start off with an example of a rattle and squeak on my own personal car that drove me crazy and was difficult to find.


Squeaks and rattles on my T/A

It’s funny that I have to go back so far and talk about my 1979 Trans Am, but this was a challenging car noises to find. My Trans Am was a sub frame car that was built in the days when this technology was relatively new. The torque of the big block 6.6 L engine and the fact that the car had removable T-tops made the entire car weak.

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1979 Trans Am

Every time the T/A hit a bump or pothole there would be a lot of body movement.

This flexing caused a creek and pop and sometimes a squeak and rattle above the drivers head. Even the slightest irregularity in the road would activate this wide range of noises.

To hunt down this noise I had to remove the headliner from the vehicle. Removing the headliner did not reveal the source of the car noise. I had a friend drive it over a bumpy road while I moved around the interior to locate the source.

To make a long story short, a bonded interior seem on the rear roofline had broken loose and was allowing the two separate pieces of sheet metal to shift over each other when the body flexed.


Car squeaks and rattles

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Mechanics stethoscope

A mechanic will often be asked to listen to sounds coming from an automobile. It is important to pay attention to the type of sound, its intensity and its frequency. The tone of the noise usually indicates the type of material that is causing it.

If the sound is dull the material is soft such as aluminum. If it is a sharp high pitch sound it will most likely be generated from an area that can vibrate quickly and made of harder materials.

Using engine noises as an example, a rod knock starts off as a soft thud that quickly becomes worse. This is because the softer bearing material reduces the noise between the 2 hardened steel objects (the rod and crankshaft). As the bearing material decreases the noise increases.

If a sound is increasing with the engines RPMs you know that the noise must be coming from something that is moving or rotating faster as the engine increases speed. This makes tracking the sound easier by reducing the possibilities.

If you can determine that the noise is occurring at half of the engine RPMs the source of the sound is from something such as camshaft or oil pumps drive that would rotate at half the speed of the crankshaft.


About strange car noises

Noise is defined as any unwanted sound. It can be both random and steady. When identifying the source of the noise you must open your mind to all the possibilities. An example would be when a vibration or noise begins traveling through other components that it is attached to.

The source of the noise may not always be originating from the location that is releasing the sound. Using the example on my 1979 Trans Am the sound appeared to be coming from over the drivers head. But in fact the broken seem was at the rear of the passenger compartment. The noise was traveling forward due to the flexing of the roofline.

Many car manufacturers will use sound insulation to prevent traveling of noises from one place to another. One of the main differences between baseline automobiles and luxury cars is the amount of sound insulation laid down at the factory.

Sound insulation material can be purchased in roles and is relatively inexpensive. You can add additional sound deadening material to your own vehicle that can greatly reduce the car noises that you hear.

This online car repair website offers many different kinds of information as well as more automotive diagnostic tips.

2 comments

  1. Thomas Automotive of NY markets a device which helps locate squeaks and rattles without requiring the technician to drive the vehicle. It is called the Rattle Tracker. The car’s tire is placed on this equipment, which contains a powerful electric motor that oscillates the suspension to recreate the squeaks in the shop. The frequency can be adjusted by remote control as the technician moves about the vehicle. Info is available at http://www.rattletracker.com or by calling (315)-923-2051.

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