If you own and drive a hybrid automobile, I’m certain one of the features that solidified your decision was the quiet nature of the machine

However, noises from your hybrid, especially when you put it in reverse, could signify one or two issues.

A particular reason your hybrid may be noisy when you reverse is the new rule for all hybrid and electric vehicles. A silent automobile could be disastrous at low speeds, which is the case in reverse and poise a danger to pedestrians, particularly those with poor vision. 

This new rule was designed especially for hybrid cars with electric vehicles, although gasoline hybrid models are not exempted. 

Besides this new rule, one thing is paramount. If your car ever develops a sound, it may become a recurring incident at some other time. 

It will be better to handle the sound in the first place without waiting for the car to develop faults. 

This article will shed light on some common causes of noise in hybrids and brands implicated.

3 Common Causes of Noise in Hybrids

As I stated initially, hybrids are incredibly silent in nature, a seemingly good feature for the ecosystem. 

But it now seems another problem has arisen. Here are a few facts why your hybrid in reverse is noisy.

Braking System of the Hybrid

All cars’ braking systems rely solely on friction to function correctly. 

New generation cars now come with technology to reduce friction, which is usually an opponent to speed, a common denominator for the modern car’s ad. 

As you make moves to reverse your hybrid, the brake pads will be at high alert. An overworking of the braking system could lead to audible sounds, especially when there is an underlying problem. 

If your car makes a clunking sound in reverse braking, a brake caliper could be off, or some components are out of order. 

Another reason could be a worn-out component. 

Dirt on the rotors or worn brake pads is usually responsible for the squealing noises.

However, not all noises from the brake pad are nasty when in reverse. A hybrid car in reverse could generate noise based on the new technology for electricity generation. 

When the brakes are applied, electricity is generated, producing whining audio. This sound is because the electric motor is working backward as you reverse. 

Such sound is typical.

Gasoline Engine Sounds

You may say this cause is also the same with the regular cars. 

Some Hybrid automobiles also come with a gasoline engine, and the sound generated that signifies a problem in reverse also applies here. 

Besides generating electricity stored in the battery, gasoline performs the same functions as non-hybrid vehicles. 

If your hybrid releases sputtering or coughing sounds on startup and become worst when you put the car in reverse, there’s cause for worry. 

A probable factor is the failing spark plugs, dirt in the air filter as the gasoline enters the carburetor, or even water in the gasoline. 

Let’s not forget your drive belt pulleys which could have lost its elasticity as you pull out of the driveway. 

Thankfully, Hybrids don’t have an alternator, so you don’t need to worry about that aspect.

Transmission Related Sounds

Most of the Hybrids on the road use a “Continuously Variable Transmission” (CVT) model. 

The car contains two pulleys and a “belt” instead of the gears seen with the non-Hybrids. 

Here’s a summary of how the CVT works; the pulleys will vary in size as the speed of the car changes, a direct factor to gear ratio changes. 

When you put your car in reverse mode, the pulley’s size will change to accommodate the rpm, meaning the pulleys will become smaller in size, and shilling audio could be heard. 

This sound is typical because it signifies a gear change, especially when you are in drive mode. The pulleys will slowly change size as the hybrid picks up speed, which is noiseless during motion.

The CVT model is another reason for the high fuel efficiency of the hybrid model.

Now, your transmission could be at fault too. If you hear a constant whining sound from the gears, more of a gear slip, then your transmission fluid may be low. A humming noise could mean the transmission pump is faulty. 

When put in reverse from neutral, a heavy clunking sound means the cross member mount has a problem and is worse if accompanied by a vibrating feeling. 

3 Great Hybrid Brands with Better Noise Controls Performance

Not all brands are noisy in reverse, especially if manufactured and released before 2019 when the national order to put a sound was made. 

Here are some Hybrid brands that are noisy when in reverse. 

Hyundai

Hyundai is the first on our list. A majority of the South-Korean-made new models now come pre-installed with a funky sound that is high enough when in reverse. 

The funny feature about this noise is that it is usually muted inside the car but irritably noisy outside. 

A good reason is that the cars are run on batteries, using the CVT transmission model, which means the engine is silent. The sound is just to alert pedestrians of a car in reverse. 

The models implicated are the 2022 Tucson, 2021 Elantra hybrid, the 2020 Sonata, etc.

Toyota

Your Toyota Hybrid could also be a culprit in the new reverse sound rule. 

The sound is more of a warning to bystanders who may not be aware of a car in reverse. Notably among them would be the visually-impaired pedestrians who rely on sound to move along the road. 

If you hear a “buzzy” sound when your car is in reverse, welcome to the new normal for Hybrid cars.

Examples of the Toyota models are the 2019 Rav4 limited edition and the 2020 Toyota Prius. 

Tesla

If you own a Tesla, chances are that your car has a sound installed, programmed to go off when driving at below 15 mph or in reverse. 

For this brand, the sound only goes louder as you increase in speed when reversing, unlike the other brands. 

You can also turn off the sound (suppose the feature is installed).

Most of the models manufactured around November 2021 fall into this category.

Conclusion

Hybrid automobiles are famous for their quiet nature when in motion. 

Some of them do not require as much transmission as with non-hybrids. With the touch of a button, your car is at high speed. 

This also poses a problem when you are in reverse with no sound, a danger to pedestrians. While some hybrids now come installed with a sound to alert pedestrians of a car in a backward motion, others are a sign of a fault hidden somewhere in the compartment that needs a fixup quickly. 

Some well-known brands are now exceptionally equipped with this tech that may sound unnecessary but important. 

Links

Owner’s Manual – Tesla

Hybrid reverse sound

Noise in reverse prius

Ticson hybrid alert sound in reverse

Quiet electric cars must make noise: new US Safety rule

Weird Noises hybrid makes and why