Your car’s braking system is one of the most critical components that can make a difference in your safety. It helps you to avoid collisions with other motorists and prevent injuries and damages that might occur while you’re on the wheel. On a daily basis, motorists navigate through highways successfully when going to and from work. However, there are times when the braking system might seem to fail leading to mild or extremely disheartening disasters. This condition is usually referred to as a brake fade. But, what is brake fade and what exactly causes it? Well, please read on as this guide will navigate deep into this topic to uncover the mystery behind brake fades and how you can potentially reduce them.
So, What Exactly is Brake Fade?
Imagine driving home from work then out of nowhere, the vehicle in front of you stops suddenly forcing you to apply the brakes. But, your car doesn’t stop immediately as you’d have expected narrowly missing the car in front.
Phew! That was close.
So, if you’re wondering what just happened, then there’s a high possibility you’ve experienced a brake fade. But, what exactly is a brake fade?
In definition, a brake fade is a temporary reduction or total loss of braking power when brakes are applied. When you apply the brakes, the brake pad and the rotor must create some mutual friction that’s responsible for the braking mechanism.
Sometimes, the rotor and the brake pad fail to generate this mutual friction leading to loss of braking power.
What Causes Brake Fade Anyway?
Your car’s brake system functions through the coordination of many components. It’s also made up of multiple components such as the calipers, pads, rotors, and the pistons. When you’re driving and suddenly hit the brakes, the brake pedals activate the calipers which in return signal the pistons to press the brake pads against the rotating rotors. This fast action causes friction which is responsible for the braking action.
Now, when the brake pads are rubbed against the rotating rotors, a lot of heat is generated which is potentially responsible for causing a brake fade. Note that the heat generated can reach temperatures ranging from 700°F to 1200°F. Such a temperature is high enough to cook a batch of cookies or even melt an aluminum braking plate.
Although brake pads can get this hot, that’s not usually the case as you only need to apply the brakes a few seconds when driving. This way, the brakes will have time to dissipate and cool down.
However, there are those circumstances where your car’s brakes will fail to dissipate such as in stop-and-go traffic, when driving downhill or when your car is overloaded.
So, in a nutshell, a brake fade occurs when the brake pads exceed their operating temperature range. The excess heat generated boils the braking system forming gas. When this gas builds up, it creates back pressure that compromises the performance of the brake caliper. This in return causes the skidding of the brake pads over the rotors causing a brake fade.
Types of Brake Fade
Now that you’re aware of what brake fade is and what exactly causes it, this section will now discuss the two main types of brake fades to keep you well informed.
Green fade is very common to most motorists and it usually occurs when new brake pads and disc rotors are installed. When a new braking system is installed, it usually takes some time for the components to get aligned. During this time (commonly known as the “bedding-in period”), your mechanic will certainly advise you to be really careful as you drive as the braking system might be a bit unresponsive.
During the bedding-in period, drivers are advised to take a tour around the city up to 500 miles. However, there is a way you can reduce this bedding period by applying brakes while driving on a safe stretch of road.
To do this, you only need to drive at 45 MPH then apply brakes to reduce the speed to about 10—15 MPH. Repeat this process for about 5 times then increase the speed to about 70 MPH. This time, apply the brakes more aggressively until you reduce the speed to about 10 MPH.
By performing such acceleration-deceleration maneuvers several times, you’ll be able to burn off some volatiles that is responsible for causing green fade.
Finally, brake pads are at some degree porous meaning they can absorb moisture from the atmosphere from the date of manufacture until they’re installed. What happens when you apply the brakes after installation is that the moisture boils producing a gas that’s responsible for brake fade.
Thankfully, with frequent accelerating and decelerating in safe roads, you can easily align the braking system quite fast while reducing moisture build-up during the bedding-in period.
Unlike green fade that’s considered to be normal, dynamic fade is very serious and should be remedied with ultimate urgency. This condition is usually caused by several factors such as;
- Using substandard brake pads
- Improper installation of the brake caliper resulting in caliper drag
- Installing brake pads and disc rotors from a different model, make, or year of manufacture
- Installing a brake system that doesn’t suit your driving style
Dynamic fade was highly prevalent in the early days as most vehicles were fitted with drum brakes. Cooling the drum brakes was quite slow meaning these vehicles would generate a lot of heat which superheated the brake shoes causing the surface of the disc rotors to vaporize leading to temporary or complete loss of braking power.
Today, major advances have been made as most modern discs brakes are vented to create a better cooling mechanism to improve their performance. So, to prevent dynamic fade, drivers should be very careful when selecting the quality, model or make of the brake pads they wish to install.
Whether it’s racing or driving a fully loaded truck, installing brake pads that can handle that extra braking demand is very critical.
Finally, remember that once you decelerate, your vehicle converts kinetic energy into friction then into heat. Since kinetic energy increases depending on velocity and the mass of a vehicle, fully loaded vehicles and those moving at neck-breaking speeds will require a high breaking demand to decelerate.
Brake Fluid Fade
Another type of brake fade that’s very common among most vehicles is brake fluid fade. This usually occurs when brake fluid overheats leading to reduced effectiveness of the braking system. You see, brake fluid is contained inside the brake calipers.
So, as the brake calipers heat up due to friction, the brake fluid too heats/boils up to form bubbles within the brake cylinders. As air increases, the total amount of fluid is reduced leading to reduced braking power. Remember, the air is less resistant hence more compressible than fluid. Therefore, instead of the pistons pushing fluid, they will instead push air through the brake calipers leading to reduced braking power.
So, to prevent brake fluid fade, car manufacturers often recommend drivers to change their brake fluids periodically after a period of about 2-years. Through this, your brake fluid will not be susceptible to debris, dirt, and water absorption.
Note that, once your brake fluid degrades due to debris and water absorption, it attains boiling point at a much lower temperature forming steam that compromises your car’s braking power.
So, Are There Ways You Can Prevent a Brake Fade?
Brake fade is a normal mechanical anomaly that usually happens when you install new components in your car’s braking system or when the caliper or the brake pads are not installed correctly. Since brake fade does happen once in a while, here are some tips that you can employ to prevent it from happening.
Use Correct Brake Replacement Components
When replacing a component in your car’s braking system, make sure that you select the right pieces that match your car’s model, make and the specific year of manufacture. You can do this by checking your car’s manual or simply by visiting your vehicle’s manufacturer website to see their recommendations.
In addition to this, make sure that the components you choose also meet your driving habits. If you’re an aggressive driver, it’s wise to select high-performance brake pads and disc rotor kits that will not fail you whatsoever.
You can opt to choose ventilated disc rotors that manage temperatures quite well or you can go for brake systems with binding resins and dimpled disc rotors as they’re known for speeding up heat dissipation and reducing the gasses that form between the brake pads and the rotor disc.
Now, although this step doesn’t reduce green fade, it does help to eliminate dynamic fade which is usually the most critical.
Treat New Brakes with Ultimate Care
When new brakes are installed, be aware of green fade as it can lead to an accident if you’re not careful. New brake pads contain a resin which evaporates as temperatures in the braking pads rises. If you’re not careful, this reaction can cause off-gassing which is responsible for temporary brake failure. Due to this reason, new brakes should be handled with ultimate care during the initial 500 miles.
Let a Professional Install the Brakes
Installing a brake pad, a caliper or a disc rotor is very easy as you only need to unscrew a few bolts and nuts. However, do not underestimate this procedure as a simple mistake along the way can be costly as it might lead to a brake fade.
For this reason, it’s wise to allow a specialist to install all the brake components for you. First, a mechanic will obviously do a great job and second, they will countercheck the entire braking system such as the brake pads, the caliper and the sliding pins to ensure they’re in order.
When you’re driving downhill, you’ll need to downshift instead of applying the brakes. This is quite easy for drivers with manual vehicles than those with automatic transmissions. However, in the case of an automatic transmission, you’ll have to apply the brakes first before you proceed to downshift.
If you’re driving on a flat road, avoid braking with constant pressure. Instead, tap the brakes slowly by slowly to give them enough time to cool down.
Get a Specialist to Diagnose Your Braking System
If you’re beyond the 500 miles limit and you’re certain that green fade is not responsible for a recent brake fade, then it’s recommended that you get a specialist to diagnose the problem. The specialist will check all the components as well as the installation of the entire braking system. He will also check the level of the brake fluid to ensure that it’s within the recommended mark.
Remember, if the brake fluid is not enough in the system, compressible gas will be developed making the brakes feel “spongy” hence less responsive.
Install Brake Coolers
During the installation of new braking components, you might ask your mechanic to install fade stop brake coolers to help improve the performance of your car. Cooler shields are usually installed between the caliper piston and the brake pad plate to transfer excess heat into an external heat sink. This helps to prevent the braking system from generating excess heat that’s responsible for a brake fade.
How do I Handle a Brake Fade?
So, if you have accomplished all the above steps and you still experience a potential brake fade, here are some last-minute hacks that you can employ to avoid a catastrophe.
Immediately use your car’s horn to alert fellow motorists about your condition. By raising some alarm, motorists ahead of you are likely to know that you’re in a serious situation and are likely to pave way for you thus avoiding a collision.
Next, try to downshift to the lowest gear. This is easy for manual transmission as you only need to use the stick. For automatic transmission, release the brake pedal to lower the car’s RPM before shifting to the lowest gear. Here, the braking power of the engine might help to slow down your car.
If your car doesn’t have an ABS, try to pump the brake pedals several times to restore the braking action.
If this doesn’t help, try to pull out of the road responsibly. If things get dire, you might be forced to use solid objects to stop the car such as bushes and small trees instead of crashing on speeding oncoming vehicles.
So, there you have it all. The next time someone asks you what a brake fade really is, I believe you have a solid explanation of what it is and what causes it. Brake fade can occur due to natural factors such as green fade or it can be caused by a faulty or incorrect installation of braking components.
To prevent it from ever happening, the best approach is to have your car checked by a brakes specialist and as always, don’t fail to choose high-standard components during installation.