Which brake drums are better, cast iron or aluminum? Read for everyone

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Rear drum brakes are still quite common (although there are now quite a few disc options). This is done for the sake of saving production on the one hand. And for longer operation on the other hand, on the consumer side (they last at least 30 - 40% longer than the opponent). However, their braking is definitely worse, and the rear disc brakes look visually better. By the way, we discussed the pros and cons here . However, drum systems are not as simple as they seem; the difference may be the material. At the moment, it is possible to distinguish between aluminum and cast iron options. We’ll talk about them now...

You can often find information on the Internet that the cast iron drum system is outdated and is not used often. But on the contrary, aluminum is advanced and is now installed everywhere! But this is not entirely true; brake drums are now used approximately 50/50. And some manufacturers are not moving away from cast iron, and there are good reasons for this. Let's talk about them.

Which brake drums are better, cast iron or aluminum? Compare and consider

When planning to update or change brakes, which brake drums are better, cast iron or aluminum, each car owner decides for himself. First of all, I would like the brake system to work like a Swiss watch - it guarantees both the life and health of the owner of the car and his passengers. And secondly: I don’t want to change the drums again. The matter, of course, is not too complicated, and is accessible to anyone who can hit the right place with a sledgehammer, and not the finger. However, this, especially if the spare parts are stuck, is long, dirty and physically expensive. So it’s better to buy spare parts that will not require replacement at least for a certain period of time. And the reliability of these parts may depend on various factors, including the manufacturer and the material from which they are made.

What to choose?

Despite the fact that the price of original consumables is slightly overpriced, in terms of quality they are the best option. In addition, such brake pads are recommended by the manufacturer and are fully compatible with a specific model.

If you don’t want to overpay, then you should pay attention to Hi-Q pads. These are inexpensive, but at the same time very high-quality consumables that are compatible with the Hyundai Accent and demonstrate good responsiveness both when overheated and when cold. We use them both front and back.

Sangsin Hi-Q is a manufacturer of not only analogues, but also original spare parts, so its quality can be trusted.

Survey

Aluminum

It would seem that a more modern and advanced material should have become a very successful competitor to traditional cast iron. Its undoubted advantages include:

Price. Nobody likes to overpay, and our people in particular. Aluminum drums cost about 2 times cheaper;

• Low wear resistance. You will have to change the drums quite often, which, in fact, you would like to avoid in the first place;
• Intolerance to temperature changes. So if, for example, you drive into a puddle on hot drums, expect problems;
• Aluminum drums stick tightly. To remove them, in most cases you won’t be able to use a regular sledgehammer. And you will have to change it often (see point 1), that is, the problem increases exponentially.
• Aluminum does not hold geometry well - the metal is still soft. So they will have to be edited regularly, which makes no one happy.

But the worst thing is the very limited choice of manufacturers and the huge percentage of defective products. People who fell for the price and ease happened to return substandard items back to the sellers with corresponding unflattering reviews. There is an opinion among drivers that if high-quality (read: imported) aluminum were available, they would put up with some of its shortcomings.

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Cast iron

The disadvantages of this material are directly opposite to the advantages of aluminum. That is, cast iron drums are heavy, expensive and rust, so they need to be painted and treated with anti-rust. However, their reliability is beyond praise: they are temperature stable (the handbrake does not stick even in deadly frosts), they do not creak, something that aluminum often suffers from, their geometry is correct from the moment of purchase and does not require adjustments throughout their service life. True, you will need to buy stronger pads for them - soft ones will quickly wear out.

Another advantage is that they practically do not stick.

: Cast iron drums that have been in service for years often do not even require the use of a sledgehammer.

As for going overboard with weight, this argument is somewhat dubious: in aluminum drums, the working surface is also filled with cast iron, that is, the gain in lightness is not so great.

An additional bonus is the ability to choose a manufacturer: cast iron drums are produced by many firms and companies.

Lumen and cast iron

SAMARA BRAKE DRUMS - ALUMINUM OR CAST IRON?

Bearded army jokes about “the lightest iron in the world” came to mind with the appearance of cast iron brake drums for Samara on sale. We have been familiar with “lumen” for a long time, but “cast iron” is a dark horse. Let's compare?

Products from Engels were entrusted to defend the interests of “ordinary” aluminum drums with cast iron inserts - they have proven themselves well. The “pure cast iron” colleagues arrived from the ATE company from Germany. Each side was represented by two reels - the rivals' business cards are shown below.

During the tests, they decided to check the geometry of the drums, measure their mass, evaluate static balancing, and also study the behavior of the products when heated and determine their static rigidity. As usual, this work was carried out by NAMI specialists.

The fact that “cast iron” would be heavier than “lumen” was clear without any weighing - but by how much? It turned out that it was approximately doubled - the mass of Russian drums was 2420 and 2460 g, respectively, and German ones - 5020 g each. Heavy, but absolutely identical!

There is more fuss with the geometry - exemplary dimensions are shown in Fig. 1. The drums were first measured in their original state, then tested with heating cycles, after which the measurement was repeated. The results are in the table. There is also data on the static imbalance of the drums.

The heating dynamics of brake pads working in tandem with our drums were determined as follows. The experimental drum was installed on an inertial stand and 15 cycles of successive braking were carried out in the speed range from 120 to 60 km/h at a pressure in the stand drive of 50 kgf/cm2 with an interval of 45 s. What happened with sequential temperature measurements is clearly depicted in Fig. 2.

Each of the graphs shown is based on the average heating results of two drums of both types. It is easy to see that the difference in the heating dynamics of aluminum and cast iron products is insignificant: after the 15th braking, the “lumen” gained only five extra degrees - this fits into the measurement error.

Aluminum brake drums

Now they are the most advanced. Why? Yes, they simply weigh little, and manufacturers are trying their best to lighten the weight of the car and, in particular, reduce the load on the axle.

Therefore, this material is now being used more and more often, what other advantages are there:

• As I already wrote, this is weight. Aluminum can weigh up to 50% less than the same cast iron version.
• Price. Not to say that they were cheaper just like that, after all, they are non-ferrous metal. But due to the mass, the difference in price is quite significant. About 30% cheaper.
• Cooling. This is really a big plus, we all know that during prolonged braking, say in the city, the discs and drums literally get hot. Aluminum conducts heat well, meaning it heats up quickly and cools down quickly. Therefore, drums made from it perfectly remove heat and cool quickly enough. Also, you can often see ribs on them, for even greater heat dissipation. It is worth noting that the more the drum heats up, the more effective the brakes decrease, and the pads simply begin to “float”. Cooling saves the situation and efficiency is maintained.
• Corrosion and aesthetic appearance. Yes, it should be noted that aluminum practically does not show any signs of rust or other decay. Thus, the outer and inner surfaces always remain clean. It is practical, and also aesthetically pleasing; there is no need to tint or maintain it. This is definitely a plus.

Kinds

Let's consider the types depending on the installation location:

1. Front. Installed on the front axle.
2. Rear. Installed on the rear axle.

Let's consider what types of brake drums there are depending on the material of manufacture:

1. Aluminum. They are more popular, they are lighter than cast iron, cost a little less, heat up poorly and cool down quickly, which is an important factor in the operation of the braking system. It practically does not suffer from corrosion and has a more presentable appearance. The disadvantages include rapid wear, they are fragile, difficult to remove, they “stick” to the surface.
2. Cast iron. Several times heavier than aluminum, but much stronger. They do not stick so much and do not deform under temperature overloads. Less effective in braking, heavy.

The best brake drum manufacturers

The top manufacturers of the highest quality brake drums are based solely on the experience and reviews of car owners.

ZEKKERT

Description. The young Chinese company ZEKKERT produces automobile filters, elements of brake and steering systems, as well as drives, hinges and supports. The concern's spare parts are characterized by a good price/quality ratio.

The company's central office is located in Germany, in the city of Munich. Production facilities are located in China. The brand not only produces, but also packages spare parts from other concerns. Over 8,000 product items are supplied to the European automotive market.

All products comply with ISO/TS 16949 quality standards.

The components are tested in special centers.

ZEKKERT drums have an excellent appearance. The manufacturer does not spare lubrication, so the product packed in the bag almost floats in oil.

The components are made of iron and painted black. The manufacturer places special emphasis on reducing the weight of the drums without sacrificing the quality of the alloy. The metal undergoes microstructure control and testing for strength and hardness.

During operation, the brake elements do not emit extraneous noise, as they have precise geometric dimensions. ZEKKERT's arsenal includes brake drums for Skoda, Volswagen, Mazda and other common brands.

Life time. ZEKKERT provides a warranty for 2 years from the date of installation of the part. The company is ready to replace defective spare parts with others. The service life of the drums is 100,000-120,000 km.

Pros of ZEKKERT

1. Affordable price.
2. Good appearance.
3. Long service life.

Cons of ZEKKERT

1. There are deformed parts.

AUTOREAL

Description. Car owners note the high quality of components. During operation, the drums do not knock, and braking remains uniform. The manufacturer has worked hard to reduce the braking distance by 10%.

Russian brake drums meet technical requirements. The material used to manufacture the parts is SCh-25 cast iron.

It is worth mentioning that AUTOREAL is the first company in Russia to produce relatively lightweight cast iron drums for the rear brake. The production uses advanced casting and machining technologies to produce parts of precise dimensions without the need for additional balancing. The components are light in weight.

Solid parts last longer due to the absence of inserts that fall off in high temperatures. The cast iron component does not deform during sudden braking.

Life time. The regulated service life of AUTOREAL drums is 120,000 km. The components are installed on domestic VAZ and GAZ models, as well as on Chevrolet, Daewoo and others.

Pros of AUTOREAL

1. No vibrations.
2. Uninterrupted operation over tens of thousands of kilometers.
3. Resistance to deformation.

Cons of AUTOREAL

1. Heavy weight compared to aluminum counterparts.

PILENGA

Description. Its history began back in 1947. Today the concern supplies brake discs and drums to the assembly lines of large automobile factories in the USA (Harley Davids, Chrysler) and Europe.

The company's production facilities are located not only in Italy and Japan, but also in other countries in Europe, Asia, and America.

All products comply with ISO 9000-4 quality certificate.

35% of all components supplied to the market are discs and drums, and 65% are blanks for cylinders, clutch elements, pins and racks. The quality of spare parts is controlled by the head office and independent agencies.

The company's own research and development center is constantly working on the development of optimal alloys of ferrous and non-ferrous metals.

During the production process, a unique computer program is used to control steel cooking, recording the slightest deviations from the given recipe.

The components are made of cast iron steel. High quality alloy and precise geometry allow the part to be used in any weather. At the same time, the driver will not hear any grinding or extraneous noise.

Life time. PILENGA drums are sold individually or in pairs. The service life is 5 years.

Pros of PILENGA

1. No vibrations.
2. High-quality braking.
3. Great resource.

Cons of PILENGA

1. Subject to corrosion.

TRW

Description. Brake drums from TRW Aftermarket cover 46.6% of the European automotive market. The manufacturer has over 350 modifications in its arsenal, represented by options with built-in bearings and bimetallic structures.

Description

Brake drums were designed back in the 19th century. At the beginning of the 20th century, the design underwent significant changes. This device also functions as a hand brake. Drum brakes compare favorably with disc brakes not only in terms of savings in production, but also in greater efficiency and longer service life.

Design

The following elements are found inside:

• brake pads (each manufacturer has its own composition, they keep it secret);
• one or more hydraulic cylinders;
• protective disk;
• retainer;
• tension springs;
• hairpins;
• self-feeding mechanism;
• block spacer;
• pad supply mechanism.

Principle of operation

When you press the brake pedal, pressure occurs in the working fluid system. It acts on the piston of the brake cylinder, the latter element actuates the brake shoe, which is located on the sides and is in close contact with the drum. Accordingly, the speed of rotation of the part decreases and due to this the speed of the car decreases. Modern technologies provide the fastest possible braking, regardless of the condition of the road surface.

Pros:

• inexpensive to manufacture, much cheaper than disk options;
• the resource is 30-40% greater than that of disk drives;
• less often have to be changed.

Minuses:

• brakes worse compared to disc ones;
• become dirty inside.

Rating of quality brake drums for 2022

The rating includes the best models, according to buyers. The popularity of the models, their reviews and consumer reviews were taken as a basis. The rating was divided into 2 large groups: domestic manufacturers and foreign manufacturers.

Models from a foreign manufacturer

BM-MOTORSPORT DR6035 cast iron, 203 mm

High quality products are achieved through the use of modern production technologies and innovative equipment. The part has high resistance to wear and overheating, and a long service life. Average price: 1701 rub.

BM-MOTORSPORT DR6035 cast iron, 203 mmAdvantages:

• quality material;
• trusted manufacturer;
• durability.

Flaws:

• not identified.

CharacteristicsDescription

TRIALLI TF015132 /76187 2 000

The cast iron drum of a well-known international company has high wear resistance and resistance to overheating. Installed on the rear axle. The diameter of the central hole is 52. The inner diameter of the drum is 203 mm, the outer diameter of the drum is 234 mm. Average cost: 1710 rub.

TRIALLI TF015132 /76187 2,000Advantages:

• optimal price-quality ratio;
• innovative production technologies;
• durability.

Flaws:

• without bearings and ABS rings.

CharacteristicsDescription

AC Delco 19372219

An American company with a long history of development, it uses its own innovative developments and advanced technologies to produce high-quality products at low costs. They produce spare parts for both trucks and cars. Average cost: 3184 rub.

AC Delco 19372219Advantages:

• long warranty from the manufacturer;
• innovative manufacturing technologies;
• availability.

Flaws:

• not identified.

CharacteristicsDescription

HERTH-BUSS J3401030

The model's hub diameter is 52 mm, height 76 mm, diameter 203.3 mm. Manufacturer from Germany. The company guarantees the high quality of raw materials and the durability of its products. Compatible with cars: NISSAN MARCH III, NISSAN MICRA C+C, NISSAN MICRA III, NISSAN NOTE, etc. Cost: 5508 rub.

HERTH-BUSS J3401030Advantages:

• perfect compatibility with NISSAN cars;
• long service life;
• quality raw materials.

Flaws:

• not identified.

CharacteristicsDescription

METACO 3070026

METASO is a dynamically developing company with 25 years of experience in the production of automotive parts. All products undergo mandatory testing to ensure compliance with international quality standards. Manufacturer's warranty up to 3 years. Cost: 2990 rub.

Criterias of choice

Tips on what to look for when choosing:

1. Material. If you plan to lighten the weight of the car and the load on the rear axle, then choose an aluminum drum, but if you need durability and reliability, opt for the cast iron option.
2. Which company is better? When choosing, the model and make of the car are important; brake drums from domestic and foreign companies have the same functionality, so when choosing which one is best to buy, focus on your needs and capabilities.
3. What is the price. Cost will vary depending on brand recognition, delivery and material of manufacture. On average, the price range ranges from 500 rubles to 8,500 rubles. Budget models will be less durable and more efficient, but you shouldn’t overpay just for the brand either.
4. Reliability. Be sure to check the compliance of the purchased product with international quality standards. Regardless of where you purchase, ask the seller for all the necessary documents and certificates. It is also important that all products pass all necessary tests for balancing, weight, geometry, static stiffness, heating behavior, etc. Your health and your life depend on the reliability and efficiency of the system.
5. Original. Try to purchase original spare parts for your car; cheap counterfeits (analogs) may not fit the technical parameters, or have low performance, and may not do the job, then you will overpay for a repeat purchase.

Which brake drums to buy

The main difference between the drums presented on the automotive market is the material used.

The components are made of cast iron and aluminum. Car owners have different opinions about which ones are better.

Let's try to understand the advantages and disadvantages of both options.

Aluminum

As manufacturers strive to reduce vehicle weight by making every part lighter, aluminum drums are in high demand.

Indeed, the mass of this material is 50% less than that of cast iron. This has a positive effect on the cost of the spare part, reducing it by 30%.

In addition, aluminum has good thermal conductivity, which is necessary for aggressive driving. The metal cools quickly, and if the component also has additional fins for heat removal, the drum is not afraid of any sudden braking.

Aesthetics are also worth mentioning. Aluminum will not rust and will remain clean for a long time.

But light metal also has disadvantages. The softness of the alloy promotes rapid wear, so such a drum will have to be replaced more often. In addition, aluminum strongly sticks to the original place and is very difficult to remove.

You cannot do without special pullers, since the metal is very fragile. This complicates the repair process in case of emergency situations on the road.

Therefore, if you often travel for long periods of time, it is better not to opt for aluminum brake elements.

Cast iron

Cast iron is a very strong and durable metal. But the car owner will have to sacrifice the lightness of the suspension.

The alloy does not stick often, and even if this happens, you can beat it off with a simple hammer.

The drum will survive this without deformation. And the most important advantage is that cast iron does not lose its geometry at high temperatures.

But among the disadvantages it is worth mentioning poor thermal conductivity, since such drums take a very long time to cool down.

In addition, cast iron is highly susceptible to rust, which is why it loses its aesthetic appearance.

When choosing a drum, take into account the parameters of the car and the nature of your driving.

Sources

• https://zapchasti-isuzu.ru/granta/chugunnye-ili-alyuminievye-barabany.html
• https://autoflex59.ru/2021/07/06/tormoznoj-baraban-vaz-2114-kakoj-luchshe/
• https://vyborok.com/rejting-luchshih-tormoznyh-barabanov/
• https://SpecTorg.su/obzory/kakie-luchshe-barabany-chugun-ili-alyuminij.html
• https://kakvybrat3.ru/luchshie-tormoznye-barabany-vaz-2110-12/

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So which is better?

What to choose in the end so as not to make a mistake? Guys, I’ll say that very few people now change aluminum to cast iron in drums or vice versa, most likely the replacement will be with disc brakes (they are really better), and ventilated or even perforated , it has been proven that with these the car brakes 15 - 20% more efficiently.

And the choice between these two, I personally would fall on cast iron, but it needs to be tinted, and it’s heavier, a pair is about 8-10 kilograms, but it’s more reliable and easier to remove. This is my personal opinion.

I’ll end here, read our AUTOBLOG

(
13 votes, average: 4.38 out of 5)

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Battery VAZ / Bogdan / 2110 / 2111 / 2112

Standard battery

A battery is installed on the Priora from the assembly line; this battery production company has proven itself well in the market. The products of this company, when used correctly, easily overcome the milestone of 5 years of active work.

Characteristics of a standard battery

Starting current

An important parameter is the starting current. This characteristic refers to the amount of energy that the battery can supply at one time. From the factory, cars of the brand in question are equipped with a battery with a rating of 425 A. This figure is small; such a battery cannot have a good stable start in cold weather.

The optimal solution is to install a battery with a starting current of 450 A or more. This parameter does not affect charging or operation in any way. The only drawback is the relatively high cost. Separately, you need to dwell on the manufacturer. The optimal solution would be to purchase:

• Multu,
• Varta.

The first is resistant to self-discharge at low temperatures. It will be possible to start the engine even at -400 C. Its only disadvantage is its relatively high cost. Varta will be somewhat cheaper. The battery is also expensive, but slightly cheaper than the Multu. When choosing, you need to focus primarily on the equipment parameters.

Reasons for battery failure

There can be many reasons for battery failure. Below is a list of reasons:

• Overcharge. Occurs due to a faulty car generator.
• Overheat. Most often it occurs in hot summer months; the temperature of the electrolyte exceeds the permissible values, which leads to damage to the battery plates.
• Low voltage in the car network. Occurs due to a malfunction in the generator.
• The battery is completely discharged. Occurs due to a broken alternator belt or when the side lights are on and the engine is off.
• Freezing. Occurs in winter if the battery is left in the cold for a long time.

TREASURE IN THE GARAGE

V. Krivosheev, Samara

The reason for sending advice was a story about resource tests of editorial Largus. It mentioned that the front stabilizer mounting bolts were badly damaged by corrosion. For about thirty years now, I have been using a proven product - Movil - to protect threaded connections, including when repairing suspension. Fasteners treated with it can be unscrewed freely even after many years. The shelf life of this drug is almost unlimited. Even slightly thickened, it also reliably protects the fasteners. There is only one drawback: if it gets on your hands, you cannot remove it without a solvent.

Battery light is on

On the dashboard of the Lada Priora there are a large number of different indicators indicating any malfunctions or the state of the engine. Quite often it happens that a red lamp with a picture of a battery may light up on the dashboard.

Design features

Many modern and not so modern cars and trucks, such as Kamaz (a very popular truck) or Gazelle, often have a rear braking system. It consists directly of the brake drum itself, as well as the so-called pad routing mechanism.

Moreover, in such a system it is the car brake drum that is the key component. The process of stopping the vehicle is realized due to the fact that contact between the drum and the pads begins when the driver presses the corresponding pedal. This activates the process of mutual friction, thereby reducing the speed and finally stopping the car. Drum mechanisms are usually based on high-strength cast iron.

Source

Difficulties during assembly

Let's return to dismantling the brake mechanism. It may happen that as a result of wear, a shoulder forms on the inner surface of the brake drum, which will prevent dismantling. The drum will still have to be removed, and after that it is necessary to measure its internal diameter. Acceptable dimensions for VAZ 2108 are 200-201.5 mm. If the diameter is larger, the drum must be replaced. If the size is within the acceptable range, then in order to remove the collar, it is enough to arm yourself with a file, install the drum on the front hub with the working surface facing outward, start the engine and engage first gear.

The drum will rotate, and using a file and sandpaper it is easy to level the bead with the work surface. After this, you need to achieve a smooth surface without marks or burrs, but after grinding it is worth measuring the inner diameter of the drum again. If the diameter is larger than normal, then there is a possibility of loss of strength, so it is better not to take risks.

In general terms, this is all you need to know about the VAZ 2108 drum brakes in order for them to provide reliable braking.

Lumen and cast iron

LUMEN AND CAST IRON

SAMARA BRAKE DRUMS - ALUMINUM OR CAST IRON?

Bearded army jokes about “the lightest iron in the world” came to mind with the appearance of cast iron brake drums for Samara on sale. We have been familiar with “lumen” for a long time, but “cast iron” is a dark horse. Let's compare?

Products from Engels were entrusted to defend the interests of “ordinary” aluminum drums with cast iron inserts - they have proven themselves well. The “pure cast iron” colleagues arrived from the ATE company from Germany. Each side was represented by two reels - the rivals' business cards are shown below.

During the tests, they decided to check the geometry of the drums, measure their mass, evaluate static balancing, and also study the behavior of the products when heated and determine their static rigidity. As usual, this work was carried out by NAMI specialists.

The fact that “cast iron” would be heavier than “lumen” was clear without any weighing - but by how much? It turned out that it was approximately doubled - the mass of Russian drums was 2420 and 2460 g, respectively, and German ones - 5020 g each. Heavy, but absolutely identical!

There is more fuss with the geometry - exemplary dimensions are shown in Fig. 1. The drums were first measured in their original state, then tested with heating cycles, after which the measurement was repeated. The results are in the table. There is also data on the static imbalance of the drums.

The heating dynamics of brake pads working in tandem with our drums were determined as follows. The experimental drum was installed on an inertial stand and 15 cycles of successive braking were carried out in the speed range from 120 to 60 km/h at a pressure in the stand drive of 50 kgf/cm2 with an interval of 45 s. What happened with sequential temperature measurements is clearly depicted in Fig. 2.

Each of the graphs shown is based on the average heating results of two drums of both types. It is easy to see that the difference in the heating dynamics of aluminum and cast iron products is insignificant: after the 15th braking, the “lumen” gained only five extra degrees - this fits into the measurement error.

To evaluate the effect of temperature on the deformation of brake drums, four more heating cycles were carried out with similar braking parameters, reaching 250°C. After each such cycle, the drum was cooled to room temperature and only then measurements were continued. Dimensions B and D, which are affected by temperature, are also listed in the table. Note that the geometry of the drums remained virtually unchanged after heating - some difference in the “before and after” results does not exceed the acceptable error limits. But the static imbalance was frankly upsetting: the excellent results of the “usual” aluminum drums looked somehow impolite against the backdrop of the outright failure of the foreign guests. Of course, everything can be balanced, but where is the vaunted German pedantry, accuracy and other advantages?

The static stiffness of the drums was determined as follows. A VAZ 2108 brake mechanism was installed in the brake drum, and “brake fluid” was supplied to its brake wheel cylinder under pressure - first 10 kgf/cm2, and then 100 kgf/cm2. It is clear that in the second case, the cylinder pistons moved away from each other by a greater amount, since as the pressure increases, the drum deforms more. And if so, then more liquid would fit in the cylinder - all that remained was to measure this difference. This was done: the result was 11% in favor of “cast iron”.

Results

But everyone has their own final opinion on which brake drums are better, cast iron or aluminum. Many believe that there is no difference at all, although 8 kilograms in weight and half the price somehow do not fit into the concept of no difference. Some people suggest not taking the cheapest aluminum - they say you won’t encounter most problems, but the average one is quite good for the price. And there are people who are sure that the choice between cast iron and aluminum is not necessary at all, since the coolest of all are disc drums, for which they need to save money.