Why Is Radiator Fan Shaking?

The radiator fan is an essential component of a vehicle’s cooling system, and it’s important to take the necessary steps to keep it running in peak condition. Unfortunately, sometimes things can go wrong, and one of the more common issues is a radiator fan that shakes. This blog post will explore the possible causes of a shaking radiator fan and the steps you can take to rectify the problem.

Dorman Radiator Fan

Common Causes of Radiator Fan Shaking

Problems With the Fan Motor

A fan motor is responsible for spinning the fan’s blades, drawing in air from the radiator, and pushing it out into the car. If the motor isn’t functioning properly, the blades may not spin properly, causing the fan to shake and vibrate.

The motor is connected to a fan blade, which spins when the motor is turned on. As the fan blade spins, it draws in air from the radiator and pushes it out into the car. If the motor isn’t working properly, the blades may not spin properly, resulting in the fan shaking and vibrating.

Loose Fan Blades

When a radiator fan shakes, it can be a sign of a serious problem. Loose fan blades, in particular, can cause a radiator fan to vibrate and shake. This is because loose fan blades are not properly balanced and cause the fan to wobble and vibrate as it spins. This can cause excessive wear and tear on the motor and bearings, leading to premature failure. If a fan is shaking, it’s important to check for loose fan blades and repair them before the fan fails.

Loose fan blades can cause the radiator fan to shake for several reasons. The most common reason is that the fan blade needs to be properly secured to the fan hub. This can happen if the screws that attach the fan blade to the hub are loose or missing.

In other cases, the fan blade may be damaged or cracked, causing it to wobble and vibrate. Another possible cause of fan shaking is when the fan blade is bent or warped. This can happen if the fan is exposed to extreme temperatures, as in the case of a car parked in the sun.

Clogged Airways

Clogged airways can be a major cause of radiator fan shaking. Radiator fans are responsible for keeping the engine cool and preventing it from overheating. If the airways become clogged, the fan cannot circulate air effectively, leading to a shaking fan.

Clogged airways often occur due to dirt, dust, and another debris buildup. Over time, dirt and debris can accumulate in the airways, restricting airflow and making it more difficult for the fan to circulate air. This can cause the fan to shake as it struggles to move the air through the clogged airways.

There are a few ways to check if clogged airways are causing your radiator fan to shake. The first is to check the radiator itself. If there’s a buildup of dirt or debris, it’s likely the cause of the fan shaking. You can also check the air filter, as a clogged filter can restrict airflow and cause the fan to shake.

Poor Cooling System

In most cases, radiator fan shaking is caused by a poor cooling system. Several things can cause this, but most often, it’s due to a lack of coolant in the system. The fan will start to shake when the coolant levels become low due to the lack of air circulation. Other causes of fan shaking are dirty or damaged cooling components, such as radiators, coolant hoses, and thermostats.

It’s important to note that radiator fan shaking is not the same as engine shaking. An issue usually causes engine shaking with the engine itself, such as a misfire or a leak. Radiator fan shaking is primarily a symptom of an issue with the cooling system itself.

When dealing with radiator fan shaking, the first step is to check the coolant levels. If the coolant levels are low, you’ll need to add more coolant to the system. You can do this by purchasing pre-mixed coolant from your local auto shop or mixing coolant and water yourself.

Once you’ve checked and added coolant to the system, you should inspect the other cooling system components. Look for any signs of dirt or debris buildup, which can interfere with the airflow. Additionally, examine the hoses and thermostat for any damage or signs of wear. If you find any of these issues, you should replace the component as soon as possible.

Loose Mounting Bolts

Radiator fan shaking can be the result of loose mounting bolts. These bolts are tasked with keeping your radiator fan secure, and when they become loose, the fan can shake due to the vibrations that come from the engine as it runs. The shaking can also occur if the radiator fan is not mounted correctly or if the fan itself is unbalanced due to a worn-out bearing or another internal issue.

Regardless of the cause of the shaking, the most important thing is to identify the source and rectify the problem as soon as possible. If you suspect your radiator fan is shaking because of loose mounting bolts, then the first step is to check the bolts and ensure they are tight and secure. If they are loose, you will need to tighten them up using a wrench or socket. If they are already tight, you may need to replace them with new ones.

Broken Bearings

When a car runs, the fan motor spins to move cool air through the radiator. The fan motor is attached to the fan blades by small bearings. If these bearings become worn or damaged, they can cause the fan to shake or vibrate. This can cause an annoying sound and can even lead to damage if left unchecked.

The most common cause of broken bearings in the fan motor is a lack of lubrication. The bearings are made of two small metal balls encased in a lubricant. Over time, this lubricant can wear away, and the bearings can become dry and damaged. If the bearings start to wear down, they can cause the fan to shake and make a noise.

To fix broken bearings in the fan motor, you will need to replace them with new bearings. This can be a difficult and time-consuming job, so it’s best to take your car to a professional mechanic. They can properly assess the damage and determine the correct bearings to install.

Solutions for Radiator Fan Shaking

Several solutions can help alleviate this issue before it gets out of hand. Here’s a look at some of the best ways to fix radiator fan shaking.

A. Replace the Fan Blades

If the fan blades are damaged, they will need to be replaced. It is important to check for any cracks or breaks in the blades before you attempt to replace them. If the blades are cracked, you will need to replace them with new ones. If you don’t think the blades are too badly damaged, then you may be able to use a fan blade straightening tool to help straighten them out and fix the shaking.

B. Tighten the Mounting Bolts

When a fan is shaking due to loose mounting bolts, you need to tighten them up. Make sure you use a wrench to tighten the bolts and avoid over-tightening them. If the bolts are too tight, it could damage the fan motor and cause further problems.

C. Replace the Bearings

If you find out your radiator fan is shaking due to worn bearings, you will need to replace them. This is an important step, as worn bearings can cause much more serious issues, such as fan-bearing failure. Make sure to always use high-quality bearings when replacing the old ones.

D. Clean the Fan

A vacuum cleaner can fix a clogged fan to suck out the dirt and dust. Ensure to avoid spraying any liquids onto the fan or motor, as this can cause further damage.

How Do You Know if Your Radiator Fan Is Going Bad?

To understand what’s going on with a radiator fan, you must first understand what a radiator fan does. A radiator fan is designed to blow air over the radiator to cool the engine. The fan blows air across the radiator’s fins, which helps dissipate the heat more efficiently.

So, how do you know if your radiator fan is going bad? The most obvious signs are if the fan is not spinning or making an unusual noise. The fan should spin at a constant speed whenever the engine is running, so if it’s not spinning, that could be a sign that the fan motor is failing.

Another sign that your fan could be in trouble is if it’s making an unusual noise. This could signify a mechanical issue, such as a worn-out bearing or a loose fan belt. If you hear a loud screeching sound, it’s probably time to replace the fan.

If you notice any of the above signs, you must take your car to a mechanic as soon as possible to get the radiator fan checked out. It’s much better to catch the problem early to avoid further damage to your engine.


A shaking radiator fan could be caused by various factors, ranging from a faulty electrical connection to a clogged cooling system. As such, it is important to inspect the fan and its surrounding components to determine the exact cause of the shaking before taking any corrective action. If the issue is minor, it may be possible to make the necessary repairs yourself. However, if the problem is more serious, it is best to contact an experienced mechanic.

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