Because it's cheaper to produce. And that may not be so bad since it's cheaper for you as well, to maintain at least.
They are also smaller in dia (not width necessarily) for the same braking force when compared to discs. This is due to the fact that the entire surface of the brake pads press against (and at) the circumference (in an axial direction). If you have alloy wheels and brakes are visible, then they might look a tad bit tiny compared to a similar class car employing disc brakes. So , if you're looking for street creds.. painting them red may not really..
Since the pads press against the drum shoe in an axial direction, they have a tendency to stick on/force the pads into full contact. This effect reduces the need for brake assist mechanisms, especially on smaller cars where it can be done away with (again, a plus for the manufacturer). Consequently, this effect, which affects the response time, could possibly be one reason why their use with ABS and similar systems is rare.
Drum brakes do not dissipate heat as well as disc brakes (open and exposed) which quite simply is its biggest disadvantage over disc brakes. This precludes its use from performance applications, though, there are exceptions.
As other answers have pointed out, this may not necessarily effect you in emergency braking situations as most of the weight shifts towards the front of the vehicle and hence most of the braking is done by the front brakes (discs in your case). This, of course is assuming that the car is pointed in the direction of travel. High speed pursuits/get-aways in reverse gear might require a different setup (fast and the furious. anyone?)
Some clarifications
Drum brakes do, in fact, have more moving parts than disc brakes, and do have a more complicated mechanism
Can be adapted easily for mechanical/cable linkages , making their use popular for parking/emergency brakes
Brake drum sold by Frontech China
We cannot deny that disc brakes are literally running the automotive industry. Most vehicles depend on this type of braking system . Disc brakes came to replace drum brakes which have been used for ages. Despite the massive popularity of disc brakes, drum brakes are not going anywhere. They are here to stay. You are mistaken to think that drum brakes are for old cars. Do you know that even modern and sophisticated cars still have drum brakes?
While disc brakes are mainly used on the front wheels, the rear brake system of most modern cars is powered by the drum brake. So, why are car manufacturers still using drum brakes yet disc brakes seem to be easily available? Why don’t they just use the rear disc brake? In this article, we are going to see the reasons why modern cars still have drum brakes.
How a brake drum works
There is always a never-ending argument between disc brake vs disc drum.
One of the key points of arguments is effectiveness.
Are disc brakes more effective than brake drums?
To be precise, the answer is yes.
The effectiveness of a disc brake is due to friction management.
The front pads ensure that the heat generated from the friction is dissipated effectively.
Heat dissipation on the rear drum brakes is not very effective..
Front discs and pads can work well regardless of the weather condition.
They will still provide a firm grip even when they are wet.
The rear drum brake parts can be affected negatively by wet conditions.
Wetness makes them lose grip easily.
To create a balance, brake drums are used on the rear wheels while disc brakes are for the front wheels.
Its only performance-based vehicles that have rear brake rotors.
Brake disc
We have seen that dis brakes are superior to drum brakes in almost all the spheres.
Whether you buy OEM brake pads or the aftermarket brakes, you can be sure of enjoying a couple of advantages.
However, this does not mean that disc brakes are flawless.
They also have some disadvantages.
One of the cons of disc brakes is they are quite noisy.
Because of their working mechanism, disc brakes tend to produce squeaking and squealing sound when in operation.
Of course, such noise can be quite annoying.
Another disadvantage of disc brakes this they are prone to warping.
The excellent performance level that you can get from disc brakes means that the brake pads are subjected to extreme friction.
Given that the brake pads directly press against rotors, they are subjected to extreme friction.
The pricing can also be a key disadvantage.
Brake discs are more expensive than brake drums.
After all, there is always a price to pay for an excellent performance.
Brake drum from frontech
Yes, drum brakes are much cheaper than disc brakes.
However, this does not mean that drum brakes are made of low quality material.
The price difference is mainly determined by the cost of the manufacturing process.
This means that it is cheaper to manufacture drum brakes than it is with the disc brakes.
Drum brakes don’t have many moving parts like disc brakes.
On the other hand, brake disc manufacturers in China use several components to come up with a functional brake disc.
The materials used on brake pads also make the cost to be high.
Ceramic brake pads in China are relatively expensive.
To get the exact figures in prices, contact brake pads suppliers in China and you will compare prices.
Probably you are wondering whether it is worth it to buy cheap brake drums.
Given that a huge percentage of the braking force comes from the front brakes, you don’t need too much power at the rear.
You don’t have to buy cheap brake pads and discs for your rear wheels.
Instead, you just need cheap brakes that will do their job perfectly.
This makes disc brakes not an investment worth the cost.
Unless you are sure of getting cheap brake rotors and cheap brake pad replacement, rear disc brakes are not worth it.
Do you want to know why drum brakes are still used in the modern world?
Here are the top reasons that can give you clues why drum brake are not going anywhere anytime soon.
1.Cheap to manufacture
Let’s face it, car manufacturers are keen on minimizing the cost of production.
Drum brakes can help them achieve this goal since they are cheap to manufacture.
Unlike disc brakes, drum brakes are very simple.
Installing drum brake shoes to the rear wheel is not a difficult task to accomplish.
On the other hand, installing disc brake to the rear wheel is an expensive and complicated process.
Automakers will be forced to install extra drum disc brakes for parking.
These minor expenses can end up raising the price of the car.
It does not make economic sense to use disc brakes when drum brakes can do the same job.
What does this tell you about the truck brake drums?
It simply means that they last longer than the disc brakes.
The drum brake kits for trucks can serve you for quite a while before you consider doing a replacement.
3.Drum brakes make good parking brake
Drum brake kits for trucks make ideal parking brake.
This is possible because of the wedging action that is emanating from the car brake shoe.
They offer a tighter grip for parking than what auto brake rotors can do.
We cannot deny that a disc brake pad kit is much safer than brake shoes.
However, brake drums still provide some level of safety.
This is mainly due to the fact that they are least affected by friction and heat.
In conclusion, we can confidently state that brake drums are not going.
Despite the fact that technology seems outdated, this brake system has a critical role to play in different types of cars.
It is only in racing cars where you are likely to find both front disc brake and rear disc brake
In other cars, drum discs will always be on the rear wheels.
Why disc brakes are still used in modern cars
Why are drum brakes cheaper than disc brakes
Are rear disc brakes worth it?