A. Automobiles use fluid (hydraulic) brakes.

When the driver steps on the brake pedal, a piston in the master cylinder is pushed, generating hydraulic pressure, which transmits amplified force to each disc brake caliper. The brake pads are then pressed against the brake discs that are linked to the wheels, and the friction generated there applies the brakes.

Within this braking system, the liquid that generates hydraulic pressure and transmits force smoothly is called brake fluid.

DOT3

DOT4

A. Brake fluid has low viscosity, small volume change due to pressure, and does not freeze at low temperatures of -50°C or boil at high temperatures of 200°C. It has the characteristics of being able to withstand various environmental changes.

If the fluid cannot maintain its performance, it cannot be used as brake fluid.

DOT3

DOT4

A. There are three types based on the ingredients. Glycol-based brake fluids are the most common because of their excellent brake fluid properties, but there are also silicone-based and mineral oil-based types.

There are also types based on specifications according to DOT and JIS standards.

DOT3

DOT4

A. The main ingredient is polyethylene glycol monoether, to which antioxidants and rust inhibitors have been added.

Glycol-based brake fluids absorb water and do not allow free water to exist. If free water is present, it will boil at 100°C and cause vapor lock. In winter, the water will freeze and damage parts. If it absorbs moisture, the boiling point will not reach 100°C, but it will drop slightly.

High-grade DOT4 and DOT5.1 brake fluids use borate esters of polyethylene glycol monoether, which allows them to maintain a relatively high boiling point even when they absorb moisture.

Racing vehicles, which use heavy brakes, require brake fluids with a high boiling point, low viscosity, and good responsiveness.

DOT3

DOT4

A. It is a brake fluid whose main component is dimethylpolysiloxane, and is only used in brake systems designated as silicone-based, such as some racing cars.

It has the advantage of not absorbing moisture and not damaging paint, but it also has the disadvantage of being easily affected by rubber such as brake system seals.

Also, if water gets mixed in, it will not dissolve and will remain as droplets, which can cause the droplets to boil or freeze.

If mixed with glycol-based fluids, they will separate, so they cannot be mixed.

DOT3

DOT4

A. It is a brake fluid whose main ingredient is mineral oil derived from petroleum. It is also called mineral-based or mineral oil-based.

Mineral oil is used in Citroën vehicles equipped with hydropneumatic systems, as the oil is shared by the suspension, steering, and brakes. If mixed with glycol-based fluids, they will separate, so they cannot be used together.

DOT3

DOT4

A. Brake fluid standards are generally based on the DOT standard, defined in No. 116 of the Federal Motor Vehicle Safety Standards (FMVSS).

The JIS standard is defined in JIS K 2233:2006. JIS and DOT are roughly equivalent, but there are some differences between the DOT4 and DOT5 standards.

In terms of specifications, DOT4 is ranked higher than DOT3, and DOT5 is ranked higher than DOT4, but the appropriate type varies depending on the type of vehicle, driving conditions, and other uses.

DOT3 is for small and medium displacement vehicles, DOT4 is for large displacement vehicles and for sports driving, and DOT5 is for large displacement vehicles in cold climates and for sports driving.

DOT3 JIS type 3 BF-3 Dry boiling point 205°C or higher Wet boiling point 140°C or higher
DOT4 JIS type 4 BF-4 Dry boiling point 230°C or higher Wet boiling point 155°C or higher
DOT5 JIS type 5 BF-5 Dry boiling point 260°C or higher Wet boiling point 180°C or higher
*Glycol-based products are written as DOT5.1
*DOT type 6 JIS type 6 BF-6 Dry boiling point 250°C or higher Wet boiling point 165°C or higher

DOT3

DOT4

DOT5.1

A. If air gets into the hydraulic system, the pressure is used to compress the air, resulting in a loss of braking force.

If you notice an abnormality such as the ABS frequently activating when you apply the brakes, or if the pedal feels extremely fluffy or the free play becomes smaller when pumping the brakes on a vehicle without ABS, air may have got into the system and you will need to remove the air from the brake fluid.

A. When you apply the brakes, heat is generated. If that heat is transferred and the brake fluid boils, gas bubbles can be generated.

Because the pressure of the bubbles is vapor pressure that is not due to the original volume, it is difficult to transmit the pressure from the brake pedal, resulting in a dangerous state of low braking force.

This is called vapor lock.

A. Most vehicles, whether two-wheeled or four-wheeled, can use the same brake fluid since they have the same structure.

However, brake fluid with a higher boiling point is used in cases other than driving on public roads at legal speeds, such as racing or circuit driving. Also, mineral oil-based brake fluid is used in some vehicles that share oil for the suspension, steering, and brakes.

A. If you want more reliable braking power or high braking power for racing or circuit driving, we recommend a high-grade brake fluid with a high boiling point.

A. It is the temperature at which the liquid boils. The boiling point of water is 100°C, but the boiling point of brake fluid can be as low as 140°C and as high as over 300°C.

The boiling point of a new brake fluid is called the “dry boiling point”, and the boiling point when the moisture content is 3.5% is called the “wet boiling point”.

The wet boiling point is a value that assumes that the fluid absorbs moisture from the air during use and the moisture content gradually increases.

A. To change the brake fluid, you need to jack up the vehicle and remove all the tires, as well as bleed the air and make delicate adjustments and checks.

Also, if brake fluid comes into contact with painted surfaces, there is a risk that the paint will peel off. There are no legal restrictions, but since it is a safety-related task, we recommend that you ask a repair shop or dealer to do it for you.

A. In addition to deterioration over time, brake fluid can also deteriorate depending on how it is used. Deteriorated brake fluid will change color from yellow to brown to black.

A. Deteriorated brake fluid has a lower boiling point, which not only prevents it from performing its intended function, but also makes it more susceptible to vapor lock. In addition, as it absorbs moisture, it can cause rust in the brake system and deteriorate the brake hose.

A. JIS is a Japanese Industrial Standard that certifies that a product has passed tests unique to Japan.

DOT is a US Department of Transportation standard that is suitable for measuring resistance to heat and humidity. For general driving, products that meet these standards are safe.

However, high-spec brake fluids intended for use in races or on circuits may not meet the JIS standard and may be labeled as “non-JIS standard products.”

There are also cases where the product does not meet the DOT standard.

A. If you mix them, the new fluid will inherit the performance of the old brake fluid. We recommend replacing the entire amount for both cost and performance reasons.

There are also cases where the product does not meet the DOT standard.

A. It is a liquid whose main component is ethylene glycol, and its role is to cool the engine.

Most products have functions to prevent the cooling water from freezing, improve cooling efficiency, and prevent rust and corrosion. Depending on the recommended concentration, you can easily adjust the amount to prevent freezing, overheating, etc.

A. Currently, most engines use a water-cooling system in which coolant cooled by a radiator passes through the cylinder head and cylinder block around the combustion chamber to prevent the engine from overheating due to combustion.

If the engine cannot be cooled and overheats, it will fall into a so-called overheating state, causing various problems.

A. JIS has two types of standards.

JIS Class 1 AF – Can be used all winter

JIS Class 2 LLC – Can be used all year round

A. There are several ways to classify coolants.

The types based on the percentage of concentration are established to make it easier to determine the appropriate mixing ratio with water. The appropriate value varies depending on the vehicle and region, so we recommend checking the vehicle manufacturer’s instructions or your dealer.

In addition, there are high-performance coolants that require a longer replacement period, such as long-life coolant known as LLC, and super long-life coolant (our company’s Hyper Coolant and Power Coolant), which have an even longer lifespan than long-life coolant.

A. JIS Class 1 coolant is supposed to last “one winter.” This varies depending on the vehicle manufacturer, but in the case of long-life coolants, which have become more common in recent years, you don’t need to change it for 4 to 6 years or 75,000 to 120,000 km.

A. To completely drain the old coolant and replace it all, you will need to remove and reinstall the drain bolt at the bottom of the radiator, mix it with water in the correct ratio, and bleed the air.

Also, since the main ingredient, ethylene glycol, is a substance that cannot be disposed of in general waste, we recommend that you ask a repair shop or dealer to do it for you.

A. Coolant is colored to prevent accidental ingestion and to make it easier to identify the location of a leak. Colors vary by manufacturer, such as pink, green, or blue, but they do not indicate the performance of the coolant.

A. There are no specific problems with mixing them, including TCL coolant, but since they use different additives, they may not be able to perform to their full potential, so we do not recommend mixing them.

A. There is no problem using it in Japanese cars, but we recommend that you avoid mixing it with Japanese coolant that is already in the car and that you replace the entire amount.

A. Superior coolant is originally supposed to be replaced every 6 years or 120,000 km, but if you add it to deteriorated or inferior coolant, the performance of the coolant will be close to that of the coolant before it was added. For this reason, we recommend replacing the entire amount to achieve the original performance.

A. Superior Coolant is a straight type that does not require dilution.

A. The color of the coolant is to prevent accidental ingestion, so even if the colors are different, mixing coolants for foreign cars will not affect performance.

A. The replacement cycle is every 6 years or 120,000 km.

A. Do not add Superior Coolant with water. Simply add the product directly.

A. The quality guarantee for this product is 3 years from the date of manufacture if unopened. If opened, please store the container tightly and use it as soon as possible to avoid contamination by foreign objects.

A. It can withstand temperatures down to -40°C.
Please use this product undiluted.

A. The additives used are different from those used in Japanese coolant. Superior Coolant uses organic additives, which are the mainstream additives used in coolants for European cars. Japanese coolant uses a hybrid of inorganic and organic additives, and the difference in additives is what makes it a distinctive coolant.

A. Coolant contains various additives, including rust inhibitors, but overseas coolant uses different additives than Japanese coolant due to considerations of the local environment and differences in water quality, so we recommend using special products.

A. It can be used in American cars and cars from other countries.

A. Superior Coolant has not been certified by foreign car manufacturers, but we have analyzed coolants that have been certified by these foreign car manufacturers, and use similar raw materials to achieve the same performance, so please use it with confidence.

A. Superior Coolant analyzes coolants from foreign car manufacturers and uses similar raw materials to ensure the same quality and performance, so you can use it with confidence.

A. Superior Coolant is orange in color, and if it is mixed with other colors of coolants for foreign cars, it will discolor, but this will not affect the performance of the coolant, so you can use it with confidence. We recommend replacing the entire amount to avoid discoloration.

A. We have conducted rust prevention tests on various metals based on JIS tests and confirmed that Superior Coolant is equal to or better than genuine coolants for European cars.

A. Yes, you can use it without any problems.

A. It is stable at high temperatures and has the ability to prevent cavitation, so you can use it with confidence.

A. Some products have PG (propylene glycol) as the main ingredient, in which case please avoid mixing them. Before using this product, please check the coolant you are currently using.

A. Superior Coolant uses the latest additives, so there is no problem mixing it with the latest G13 standard (2010 or later). If you are still using an older coolant, we recommend replacing the entire amount by draining the coolant.

A. As a result of our analysis, we have confirmed that Superior Coolant has superior performance in metal corrosion tests (rust prevention evaluation). If you are planning to use it in severe conditions, we recommend Superior Coolant, which has a well-balanced rust prevention effect, for greater peace of mind.

A. It is possible to use Superior Coolant in cars with an old history, but please be careful about the maintenance status of the car before using it.

A. This product meets the DOT4 standard set by the Federal Motor Vehicle Safety Standards (FMVSS), the BF-4 standard set by the JIS-K 2233 regulations of the Japanese Industrial Standards (JIS), and the Class 6 standard of the International Organization for Standardization (ISO).

Superior Brake DOT4 LV is produced in a JIS-certified factory and meets DOT, JIS, and ISO standards, so you can use it with confidence.

A. This product is a low viscosity type brake fluid that provides excellent performance for vehicles equipped with electronic devices such as ESP (Electronic Stability Program), ABS (Anti-lock braking System), and ASR (Anti-Slip Regulation) to improve safety, and is suitable for the operation of the latest brake systems. This type of brake fluid is specified for European cars in particular, and DOT4 LV is required to achieve the intended performance.

Superior Brake DOT4 LV is produced in a JIS-certified factory and meets DOT, JIS, and ISO standards, so you can use it with confidence.

A. The main difference between Superior Brake DOT4 LV and regular DOT4 is that it is a brake fluid that has better fluidity at low temperatures than products classified as regular DOT4.

The LV in the product name stands for Low Viscosity.

Superior Brake DOT4 LV is produced in a JIS-certified factory and meets DOT, JIS, and ISO standards, so you can use it with confidence.

A. Brake fluid standards include a section for measuring kinetic viscosity at -40°C to ensure that the brake system can function normally even when using the brakes in cold regions or during the winter.

Brake fluids with a low kinetic viscosity and softer kinetic viscosity are said to have better responsiveness and transmission, and Superior Brake DOT4 LV has a lower kinetic viscosity at -40°C of 628cst (representative value) compared to regular DOT4, making it a brake fluid with excellent responsiveness and transmission even at low temperatures.

A. No. There is no problem. The kinetic viscosity at high and normal temperatures is not significantly different from that of regular DOT4, so it can be used stably from high to low temperatures.

A. Some products use the name “Super DOT4” to differentiate them as “high performance brake fluids” with a higher boiling point than regular DOT4, but in reality there is no standard called “Super DOT4” and they are classified as DOT4 only.

The big difference is that “Super DOT4” does not retain the good fluidity at low temperatures, which is the greatest feature of “Superior Brake DOT4 LV”.

A. In recent years, brake fluid has a sensitive role to play, as more precise control is required due to the spread of automatic brake control devices such as ABS, EBD, TCS, etc., which are installed in most vehicles, and the evolution of these electronic devices. For this reason, brake fluid has excellent fluidity even in the severe low temperature range, compared to the normal temperature range where the kinetic viscosity is always soft, which is an important factor in activating the safety devices built into these brake systems under various conditions, and it can be said that it is ideal for vehicles with these functions.

A. Although a very small amount of fluid does evaporate, the main reason for the decrease in volume is wear of the brake pads. A certain gap is required between the disc rotor and pad, and between the brake drum and lining. An automatic adjustment device works to keep this gap constant.

In other words, “Pads and linings wear out ➡ The gap becomes larger ➡ Automatic gap adjustment (cylinder piston advances) ➡ The amount of oil in the cylinder increases ➡ The fluid level in the reservoir tank decreases.” In particular, disc brakes have a large cylinder diameter, so the fluid level changes greatly due to pad wear.

A. We recommend refilling with brake fluid of the same performance (product), but if it is a glycol-based (non-mineral oil-based) product, you can refill it if the fluid is less than the lower limit line (Min). However, if you refill with a fluid of a different performance, the performance will be pulled by the brake fluid with the lower performance. For this reason, we recommend replacing the entire amount in order to maximize performance.

A. Brake fluid is hygroscopic, so after about two years the boiling point drops and the risk of vapor lock increases, so regular full replacement is the most important maintenance, and the same is true for Superior Brake DOT4 LV. However, even if it has been less than two years since the last replacement, if the fluid has deteriorated due to the usage environment and conditions, and the color of the fluid has turned black or there is a significant discoloration other than black, please replace it sooner.

A. We recommend storing it indoors, avoiding high temperatures and humidity. Also, dirt and moisture are the enemy, so be sure to seal the container tightly. If foreign objects or moisture get mixed in and you continue to use it, it can become extremely dangerous.

A. Yes, it can be used. The yellow coloring is just a change in color over time of the additives such as “antioxidants” and “rust inhibitors” that have been added, and has nothing to do with the performance of the fluid, so please feel free to use it.

A. Some vehicles, such as the Toyota GR Supra, meet the DOT4 LV standard. This is because the engine and other power and drive systems were jointly developed with BMW and reflect the specifications and technology of European cars. The DOT4 LV standard, which has not yet been adopted in Japan, is designed to maintain performance at room temperature while being less likely to harden at low temperatures, and is becoming the standard for European cars.

A. Yes, it can be used. The yellow color is simply a change in color over time due to the additives such as “antioxidants” and “rust inhibitors” that are added, and has nothing to do with the performance of the fluid, so please use it with confidence.

A. No, there is no problem. It can also be used as a replacement for general DOT3 and DOT4.

A. No, there is no problem. It can also be used as a replacement for general DOT3 and DOT4.