Why Does Your Belt Squeal When You Accelerate And How Do They Affect Ride Quality?

Do you notice a squeaking noise coming from the belt when pressing the accelerator pedal? It tells you there are some problems with the belt (serpentine belt).

But why does your belt squeal when you accelerate? Knowing them in-depth is necessary, isn’t it? There are several reasons to create this wired squealing noise. Despite installing a new belt recently, you can still hear this.

Luckily, in this article, we have represented all the possible reasons why squeaking noise produces in time of acceleration. Also, you can learn how to stop this kind of noise without being a pro. Let’s discuss them in detail.

Why Does Your Belt Squeal When You Accelerate

The serpentine belt works a lot to tune up and regulate the power steering pump, alternator, AC compressor, and water pump. This is why you should know why this noise is coming out.

Knowing and figuring out the specific reasons why does your serpentine belt squeal when you accelerate is crucial. Otherwise, you can’t troubleshoot the issues. Here is a table including the possible reasons for the problems.

Possible ReasonsProblems
Damaged or Parched Serpentine BeltPoor engine performance or the vehicle overhears quickly and very often.
Improper Tension or failure tensioner internallyDamages the belts easily by generating tremendous heat.
Pulley MisalignmentCauses stability and tracking problems of the belt
Belt misplacementIncreased wear and quick fatigue of the belt
Bad Idler PulleyCheck engine light appears on the dashboard or the engine may overheat quickly.
Worn-out alternator BearingsFail the rotor to spin efficiently and seized up quickly
Loose Serpentine BeltCauses inadequate power to the vehicle’s water pump
Contaminated Fluid on the serpentine beltDamages the automatic tensioner

Are you eager to know about the possible reasons for this issue in detail? Here is a detailed discussion of what causes squealing belts that will help you to understand each reason properly. This way, you can fix or stop the belt squeaking noise effectively.

Reason #1: Damaged Or Parched Serpentine Belt

The first reason why does your belt squeal when you start your car is the worn-out or failing serpentine belt. This is also pointed out as one of the foremost reasons by Your Mechanic experts.

As time goes by, the serpentine belt starts to wear out like other car parts. Typically, after 70,000 to 80,000 miles, the serpentine belt starts to dry out and tends to wear out, stated Repair Smith.

This causes you to hear some unexpected noises when the belt rotates or spins. When you hear this continuously, you must understand that there is constant friction because of the aridness of the belt.

Again, hot smoke from the engine or excessive engine temperature can easily dry out the belt. Basically, this causes the belt to weaken easily and at some point, it cannot maintain the necessary tension that requires to hold the tensioner pulley accurately. As a result, it cannot hold the belt together.

Reason #2: Improper Tension Or Failure Tensioner Internally

Proper tension is essential to keep the belt noise-free and running smoothly. Improper belt tension cause slippage, which in turn produces noise. In addition, it is the main culprit in damaging the belt and assists to provide extremely high temperatures.

Consequently, the entire belt-driven components will stop functioning properly. According to Repair Smith, an errant serpentine belt tensioner can’t provide the necessary tension to grip the tensioner pulley. Plus, the wrong placement of the tensioner can cause inconvenient linkage between the belt.

Also, check if the belt tensioner is loosened or tightened. If the tensioner isn’t placed tightly, the belt noise will come when shifting the power steering wheel.

Reason #3: Worn-out Pulley Bearings

According to the GMB, defective serpentine belt pulley bearings can be another possible reason behind the squealing noise. If the above-mentioned reasons are not the exact reasons, you can check the pulley bearings right after.

When you hear some chirping or squealing noises after starting the car, it’s typical that the bearings malfunction. Note that, the pulley bearings may spin pretty genuinely, but this doesn’t mean the bearing is in good condition.

Bearings are prone to damage if there is a lack of essential grease or other necessary objects. If you left the bearings unchecked for a long and don’t grease them up, they will overheat very often. As a result, you’ll find seized bearings or they’ll explode.

Reason #4: Pulley Misalignment

A misaligned pulley or tensioner is the most intriguing cause of the alternator belt squeaking noise. You can easily understand whether the pulley is misplaced or not. The only thing you should do is rev up the engine and inspect the sound. If you experience belt vibration and the chirping noise gradually increases with engine frequency, assume the pulley must be aligned correctly.

Also, check if the pulley spinning grooves are placed correctly. Indeed, the drive belt’s pulley rotating grooves hold the belt in the right place. Pulley or tensional misplacement can lead the belt to wear or crack.

Possible Solutions: First, inspect the pulley or other related parts deeply. If you find any issues like misalignment, contact a professional mechanic. Hopefully, he will align the tensioner or pulley correctly, or replace it if required.

Reason #5: Loose Serpentine Belt

David Smith, a well-known figure as an Automotive Mechanic in Your Mechanic said,

“A loose serpentine or drive belt emits a harsh squealing noise. Simply stated, a loose belt is a telltale sign of squealing belt noise. You can understand whether the belt loosens by checking its tension and appearance.”

If the belt is too loose, an alternate will slip. Apart from squealing noise, a loose belt causes issues in the water pump that can cause the engine to be hotter swiftly.

Reason #6: Belt Misplacement Or Wrong Belt Installation

Belt misplacement causes the belt to slip and the slippage causes due to loosening drive belt tension. Wrong belt installation leads the belt to malfunction. Anyway, most belts have extreme-tension nature, so it needs to be installed perfectly for better function.

Unfortunately, if the belt is installed inappropriately, the pulley produces weird squeaking noise no matter if you have a brand-new belt.

Reason #7: Bad Idler Pulley

Now, there may be no issue with belt installation, misplacement, or even if the belt is in good condition. What do you do then? Probably there is an issue with the idler pulley. The idler pulley does a lot to keep the serpentine belt in the right places for the right tension.

And note that, the right tension means the right spin. But a faulty idler pulley can’t keep the belt in the exact place, which in turn causes the belt to slip. Finally, this is not a nightmare if you hear a rapid squeaking sound.

Reason #8: Contaminated Fluid On The Serpentine Belt

Last but not least, fluid contamination on the drive belt creates noises, including chirping and squealing. It especially occurs in an automatic tensioner and oil contamination seems rapid on it. This contamination can cause the entire drive to malfunction.

How Do You Stop Belts From Squeaking- The Ultimate Solution

It’s always frustrating to hear the squealing noise coming from the belt. Replacing the entire belt is a little bit expensive and time-consuming as well. As a result, stopping the squealing noise coming from the serpentine belt is required. But how do you get your serpentine belt to stop squealing? It’s more effortless than you think.

Way 1: Spray Fluid Or Water On The Belt

Spraying the water or any other low-cost fluid is the cheapest way to stop the belt from squealing. Though it is a temporary solution to quiet squawking noise, it works.

Therefore, you must give it a try if you are looking for something inexpensive. Just pour some fresh water into a spray bottle. Keep the belt running and diagnose the area from where the noise comes. Then, spray in the right place to stop the unwanted squeaky noise.

Using WD-40 would be an excellent choice if you need a handy dandy solution. Just spray a little amount of WD-40 on the RHIB side. This way, you can eliminate this squeaking noise in no time.

Way 2: Placing The Belt Accurately

The most squeaking or chirping noise occurs for serpentine belt misalignment. If the belt is loosened, you must tighten it.

If you have a mechanical drive belt, start with the back belt and work forward. Then, put it at the correct tension and tighten the nut.

For better and long-term fixing, you can take your car to the mechanic to reinstall or tighten it. Make sure the belt is not deviating from the right place. Otherwise, it will slip which causes an overheating problem in the belt.

Way 3: Put Some Grease On The Ball Bearings

If there is an issue with the pulley bearings, mostly, the reason is lack of grease. In this circumstance, take off the bearings and grease them adequately. Note, in some cases, greasing is not only a solution if the bearings are old. In this case, you should replace the bearings.

Way 4: Use Bar Soap

Using bar soap or dish soap is a short-term solution, but don’t think it doesn’t work. Applying soap is the fastest and simplest way to stop the squealing noise.

To do that, rub the soap on the side panel and the bottom part. Soap it up to ensure the soap saturated each corner perfectly. Next, turn the engine to check if it works or not. If not, apply more soap. Simple!

Way 5: Use Belt Dressing

Another temporary yet effective stopping process is using on-belt dressing. Remember to apply this method only if the other methods fail to fix it. According to Live About,

“Applying an aerosol belt dressing is as easy as it seems. All you need to do is aim and spray. The catch is that you have to do it with the engine running, so be very careful!”

Some folks don’t recommend using belt dressing on the serpentine belt. They recommend using belt dressing on V-belt. However, if you have no solution by hand, you can use it for short-term relief.

Frequently Asked Questions (FAQs)

How Do You Stop Squeaking When You Accelerate?

Stopping the squealing noise when accelerating depends on the type of problem. This is why you should figure out the exact reasons why the noise is coming from the belt. After diagnosing the specific reasons, take the necessary steps accordingly. If the noise is caused by the misaligned belt or tensioner align them correctly.
But if the problem is in the installation, hire an expert mechanic to do the mounting task. All in all, check the whole part related to the belt and then take a decision. It is also appreciable to change the belt and other parts if you have no problem spending extra bucks.

Is It Ok To Drive With A Squeaky Belt?

Unlike other car problems, belt squeaking isn’t a big deal for a moment. You can safely drive your car for about 2 weeks with the belt squealing. But it’s recommended to resolve the problem immediately after noticing it. If the problem is loosening the belt, you should fix the issue within a day. Otherwise, you can’t get a sound drive experience. Generally, you can drive safely with this belt except for the belt connecting the power steering pump.

How Long Will A Squealing Belt Last?

How long the serpentine belt lasts depends on you. How? It’s all about maintaining the belt properly. If you give proper care and maintain it correctly, this belt will last up to 50k miles to 70K miles effortlessly, which is almost 5 years. Most modern car uses a high-end belt to provide long-lasting service. Heat and friction are the bitter enemies against the belt. If you manage them, you will get good service from the belt. The more you care, the more you’ll get advantages.

Can You Spray WD-40 On Your Serpentine Belt?

Spraying WD (Water Displacement)-40 is a great way to eliminate squealing noise from the serpentine belt. Compared to other solutions, applying WD-40 is the most effective and time-saving option. The only disadvantage of using this ingredient is its short-term effect. A WD-40 user commented on the Garage Journal that he has been using the WD-40 for 30 years.

Final Verdict

Driving without any issues is always a fantastic thing for a driver or a car owner. Be it normal or serious problems, as a car owner you can’t expect any issues, right? Likewise, from time to time you may notice a chirping or squealing noise coming from the serpentine belt whenever you start the car or accelerate.

It is definitely a bad experience. Over time, this problem occurs even after installing a new belt. So the explanation of why does your belt squeal when you accelerate is given in this article. The primary cause is the incorrect installation of the belt.

In addition, internal parts such as bearings, tensioners, idler pulleys, or loose serpentine belts cause this problem as well. Know the exact reasons and treat them accordingly by reading this guide.

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