Should Xiao Ka choose hydraulic brakes or air brakes? It’s important to match them to the working conditions.

Even a bustling city can't do without 'clothing, food, housing, and transportation.' However, the city restrictions on large vehicles can be troublesome. This is where small truck models step in, taking on the last-mile delivery and delivering complete goods sequentially to the warehouses of major supermarkets. For us truck drivers, small trucks are not only a benefit to people but also a means to support our families. Today, we’re going to talk about two types of brakes on small trucks, providing an answer for truck enthusiasts who are buying a vehicle and are unsure whether to choose hydraulic brakes or air brakes.

▎Comparing the Strengths and Weaknesses of Components

Here, we will first discuss the respective components of hydraulic brakes and air brakes. As the saying goes, if you know yourself and your enemy, you will be victorious in every battle. By understanding their structures well, you can choose a vehicle according to actual operating conditions, avoiding resource wastage while ensuring greater comfort.

(1) Hydraulic (Oil) Brake Structure

Hydraulic brakes are quite common on motorcycles, small cars, and light trucks. This is because their structure is relatively simple, requiring less installation space. The overall structure includes: master cylinder, brake calipers, fluid reservoir, and connecting lines, without the need for other auxiliary equipment. Maintenance costs are also relatively low.

A hydraulic brake works by having the master cylinder push the brake fluid to each caliper when the brake pedal is pressed. This creates pressure in the calipers, which then either expand or clamp the brake drums to produce a braking effect. They are commonly seen in small vehicles because such vehicles require less braking force, and hydraulic brakes provide smooth braking, making driving more comfortable.

Advantages and disadvantages

According to the current mainstream model ratio, oil brakes are more common on light passenger vehicles, their load capacity is not high, and more emphasis is placed on comfort, so the braking force of oil brakes is soft, and the reaction will not be too strong, and the space required after assembly on the car is also small.

If it is assembled on a loaded vehicle, it is not recommended by individuals, because the braking force of the oil brake is weak, once the emergency braking of the heavy vehicle cannot be braked, and even I have seen card friends complain, in an emergency, step on a few brakes hard, the brake sub-pump also burst, which directly leads to the failure of the brakes, and the weak braking force is the primary disadvantage of the oil brake.

(2) Air brake structure

Compared with oil brakes, individuals will be more inclined to air brakes, after all, the driving inertia of large passenger and cargo vehicles is large, and the braking force required after the vehicle load is also relatively large, only the use of air brakes can be satisfied, but the structure of air brakes will be more complex than oil brakes, mainly composed of: air compressor, air storage tank, air circuit, push rod, pressure spring, leather bowl, brake air chamber, control valve, etc.

Some vehicles have air leakage, after the vehicle is parked for a certain period of time, the air pressure of the gas storage tank will leak, at this time the vehicle's braking system will be locked and unable to drive, you need to first shrink the air through the air compressor, and pump to "unlock" the vehicle, when pressing the brake pedal, its working principle is similar to the oil brake, which is to break the air pressure through the air pressure valve, and use the pressure of the spring to support the brake pad and rub the brake drum to brake.

Advantages and disadvantages

Compared with oil brakes, it is the opposite side, the comfort of oil brakes is good, and the braking force of air brakes is strong, the two can not be taken into account, now many light trucks are also equipped with air brakes, because the actual road conditions and operating conditions in China are still mainly loaded, and air brakes also give full play to their advantages.

However, in the later maintenance and use, the disadvantages of air brakes are also more obvious, the wear of the brake pads is relatively large, and some old cars will have "hundred" reasons for air leakage after parking, it needs to be used for a period of time to idle and pump, and frequent stepping on the brake pedal when going downhill will also lead to insufficient air pressure, which will directly lead to brake failure, and the problem of air leakage in this old car is also more difficult to solve, and the structure is more troublesome.

▎Who should I choose? Choose a car according to the working conditions

After introducing the composition and comparison of oil brakes and air brakes, I believe you also have a certain understanding of them, this time mainly talk about how to choose a small truck model, after all, the positioning of the small truck model is more embarrassing, you can choose oil brakes or air brakes, the load capacity of 1-2 tons is also there, who will be better to choose? Let's give a brief example.

Supermarket delivery: Master Ji is a driver of supermarket distribution, usually mainly going out at 5 o'clock in the morning, returning home at 7-8 o'clock in the evening, spending a long time in the car every day, his small truck model is a flying saucer to the road, equipped with gasoline engine and oil brake braking, because the vehicle is selected by the company, in actual use, Master Ji believes that usually mainly based on urban road conditions, occasionally contact high-speed road conditions, under such conditions, the braking force of the oil brake is basically sufficient, the usual load capacity is about 1 ton, and there will be no situation where the brakes cannot be stopped.

Building Material Delivery: Compared to short-distance deliveries for supermarkets, building material delivery is tougher — it’s hard on both the people and the vehicles. Master Tang runs a cement shop in the village, mainly selling bagged cement, sand and gravel, putty powder, and other materials. He usually delivers to self-built houses in villages within a few miles. For delivery, he chose a small light-duty dump truck, which is equipped with an air brake option. This is because Master Tang knows very well that rural roads are quite rough. After carrying 2-3 tons of goods, going uphill is easy but coming downhill is difficult, and without sufficient braking power, it’s hard to stop safely on a descent.

Less-than-truckload transportation: Small trucks still have many uses. There are personal-use models and commercial models. Buying a small truck to take orders on a platform, helping customers transport small parts, move house, and so on are all common situations. When doing city-to-city transportation, Master Ding also chose an air brake model because, in addition to driving in the city, he also needs to drive in suburban and rural areas where road conditions are more complex. Even though the load is not very heavy, he still feels that air brakes are more reliable. However, many models come standard with hydraulic brakes, with air brakes offered as an option for users, providing a wide range of choices.

Summary: From this perspective, both hydraulic brakes and air brakes have their advantages, and users need to choose based on their own operating conditions. For vehicles like refrigerated trucks or fruit and vegetable transport trucks, which usually carry relatively light loads and need to ensure the integrity of the cargo, a gentle hydraulic brake is more suitable, as the adequate braking force won’t feel too abrupt. 

For vehicles transporting building materials, bulk goods, etc., where the cargo weight is variable and the road conditions are rough, I would personally recommend air brakes. Looking at our national conditions, the once-popular Japanese light trucks were all equipped with hydraulic brakes, but the versions that sell well domestically are air-brake models. Why is this? Because air brakes are better suited to our road conditions. 

Another aspect is that domestic vehicles have limited durability. New models certainly don’t have issues, but after 5-6 years of use, the difference between air brakes and hydraulic brakes becomes apparent. Under long-term overload, hydraulic brakes quickly run into problems, with frequent minor faults. Against this background, air-brake systems have gradually been adopted from heavy trucks, medium trucks, and light trucks down to smaller trucks.

▎Post-Maintenance Care

When it comes to choosing between hydraulic brakes and air brakes, users are also very concerned about post-maintenance care. After all, when you buy a vehicle, you want it to run fast and smoothly, and no one wants to deal with frequent minor repairs. So, in the end, is it cheaper to maintain hydraulic brakes or air brakes? In terms of purchase cost, hydraulic brake models are definitely a bit cheaper. Can the extra money spent on an air brake model be recovered in future maintenance costs?

Hydraulic Brakes: In my experience, the maintenance of hydraulic brake models is relatively hassle-free. Apart from changing the brake fluid, you just need to pay attention to the wear of the brake discs and pads. Many small trucks have a front disc and rear drum braking system, which is highly similar to passenger cars, effectively reducing later maintenance costs.

It's important to emphasize here that vehicles with hydraulic brakes still need to be cautious after driving through water. Just because a small truck has high ground clearance doesn't mean you can drive recklessly. Brake calipers can easily get stuck after being submerged; often the first press of the brake works, but after releasing and pressing again, it becomes very hard. Components like the vacuum pump also need attention during use. For vehicles carrying standard loads on good roads, using hydraulic brakes for emergency stops is generally not a problem. However, if the vehicle is overloaded or the road conditions are poor, it could even result in situations described by some drivers, where pressing the brake all the way could cause it to fail completely. 

Air brakes: Vehicles with air brakes are usually 4,000 to 5,000 yuan more expensive than regular hydraulic brake vehicles at the time of purchase. In terms of maintenance and use, attention still needs to be paid to adjusting the brakes. The brake lines of air brake systems are relatively durable, while the parts that wear more easily are the brake drums and brake shoes. If the brake linkage does not have automatic adjustment, it will need to be adjusted manually at regular intervals to ensure consistently good braking performance.

After driving through water, the air brake needs to be gently pressed a few times to use the heat generated by friction to evaporate the moisture. Under normal use, the maintenance cost of air brakes is not higher than that of hydraulic brakes. In comparison, the braking feel when driving is safer, and the likelihood of performance degradation during prolonged braking is lower. Modern small truck models are all equipped with ABS anti-lock systems, so air brakes can be applied gradually or fully, depending on road conditions. Overall, it is cost-effective to use, provides peace of mind, and is suitable for small trucks carrying heavy loads.

▎Summary

As we all know, domestic light truck technology mainly comes from Japanese designs, and small truck technology has also largely referenced Japanese choices in braking systems. However, there are very few models still using hydraulic brakes; most have boldly switched to air brakes. Many people might think that fitting air brakes on such a small vehicle is like using a 'big horse to pull a small cart,' but that's not the case. Considering our national conditions, air brakes are actually safer, which may be what is referred to as a 'Chinese characteristic.'