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Why is it important to mix antifreeze with water?

Antifreeze contains chemicals that protect your engine against rust and corrosion, as well as freeze-up and boil over protection. Water is required to activate the chemicals in the inhibitor package. Furthermore, adding water (up to a certain point) to antifreeze actually lowers the freeze-up and heightens the boil over protection provided. A mix of 40% antifreeze and 60% water provides freeze-up protection down to -10°F and boil over protection up to 259°F. In comparison, a mix of 70% antifreeze and 30% water provides freeze-up protection down to -62°F and boil over protection up to 270°F. However, we do not recommend adding more than 70% antifreeze. Over 70% would limit the corrosion and freeze up protection and heat transfer capabilities of the antifreeze. Pure antifreeze freezes at -13°.

Can I mix ordinary tap water with antifreeze?

ASTM publishes the following recommendation for make- up water (ASTMD-4985).


Tap water is commonly used for mixing with antifreeze; however it must meet ASTM D-4985. Deionized water or distilled water is preferred as it has fewer reactive chemicals such as Magnesium, Silicate, Chloride, Oxygen, resulting in optimum coolant life and performance. Do not use water softened with salts to mix with antifreeze. Also, do not use well water as it normally is very high in mineral content.

Phoenix city water has 250pp of Chlorides or higher!

Are all recycled antifreeze basically the same?

No. Not all recycled antifreeze is created equal. Many recycling methods do not remove harmful contaminants such as soluble salts. Commonly used recycling processes such as filtration, chemical filtration, chemical filtration/oxidation, and centrifugal separation/filtration can remove large particulate but not dissolved salts.

I have heard that some antifreeze recycling processes don’t remove chlorides. Is this true? Don’t antifreezes with chlorides pose a corrosion problem for my cooling system?

Filtration alone will not remove chlorides from used antifreeze. Additional processes, such as distillation and reverse osmosis, are required to remove chlorides from used antifreeze. Chlorides, which are especially aggressive toward aluminum and can attack copper as well, and are leading contaminants for causing corrosion of cooling systems.

How does antifreeze differ from engine coolant?

Engine coolant is a generic term used to describe fluids that remove heat from an engine. Antifreeze is a more specific term used to describe products used to provide protection against freezing. Many people use these terms interchangeably, as we also do in this FAQ.

Is S48R Antifreeze/Coolants aluminum compatible?

Yes, S48R Antifreeze/Coolant is fully aluminum compatible.

Why can I not use straight coolant instead of diluting it? Will more coolant not give me better protection?

The freeze point of undiluted coolant will only be -13°C, and therefore you could have freeze point problems in the wintertime. Too much corrosion inhibitor could lead to inhibitor fallout, especially in those cases where SCAs (supplemental coolant additive) are added. Physical properties of pure coolant are not the same as premixed coolant.

Why does the directions state that distilled, or deionized, water should be used to blend coolant?

Some coolants are sensitive to hard water, which can cause some corrosion inhibitors to form insoluble salts in the water. The result is premature coolant failure. Hard water salts will deposit on hot areas within the coolant system creating insulating films, which contribute to overheating problems in the coolant system.

When should I replace my coolant fluid?

In general, follow your OEM’s (Original Equipment Manufacturer) guidelines. If you do not have a guide and are using traditional coolant, then change every two years. Extended Life Antifreeze/Coolant is every 5 years or 250,000 km. Extended Life Heavy Duty is 1,000,000 km, 12,000 hours, or 4 years, whichever comes first. It is important to note that you should check a coolant system at least twice a year. If the coolant is dirty, cloudy, or full of particulate, than the coolant system should be drained, flushed, cleaned, and refilled with FulFleet pre-diluted coolant. The reason for the bad condition of the coolant should also be determined.

What S48R Antifreeze / Coolants are best used to replace factory fill?

Fullfleet Coolants

S48R Coolants

1.Coolant colors from individual manufacturers can vary widely. The chart is meant to group similar chemical technologies, not to express that those listed are the same chemical compound. Some OEM’s have multiple coolant chemistries and colors. Consult with your technical contact for up to date information. Many OEMs will substitute alternate coolants at the customer’s request.

2.Hybrid type chemistry can vary in formulation based on manufacturer.

3.Non Nitrite, poly organic and organic type chemistries.

Why are there so many different colors of antifreeze and what should my business be using?

Colors are generally used by major companies to identify their products as a part of their marketing platform. Unfortunately as of today, there is no universal color pattern to follow. Before dye is added, all antifreeze is actually completely transparent.

Traditional green coolant uses inorganic additives and is commonly referred to as Inorganic Additive Technology (IAT). Using phosphates, or more recently silicon, traditional coolants provide a fast acting protective film known as passivation. This type of coolant is compatible with all types of coolant. However, it is not long life and should be replaced every couple of years.

In 1995 General Motors (GM) introduced a new coolant technology known as Organic Acid Technology (OAT). Most commonly referred to in America as DEX-COOL®, this coolant generally utilizes the organic acid 2-ethylhexanoic (2EH). This extended life antifreeze is typically dyed orange; however, most German cars, Mercedes, BMW, Audi, are colored blue while pre 2009 Volkswagen is colored Pink. Pre 2004, Toyota used a red OAT coolant, and then switched to a pink HOAT coolant. While these fluids extend service intervals, they do not protect as quickly as conventional green coolants.

Hybrid Organic Acid Technology (HOAT) combines inorganic and organic acid additives for long life protection. Using Silicon, fast acting, and organic acids, long lasting, HOAT provides excellent all around protection with extended drain intervals. HOAT coolants generally can replace or are compatible with conventional green coolant in older vehicles. Yellow is the common color for HOAT coolants, including G-05®. Chrysler begin using G-05 in 2001 and Ford followed shortly after in 2002. Many Japanese models also use this coolant chemistry: Post 2004 Toyota’s and post 2009 Volkswagen’s are colored pink, Honda coolant is blue and Mitsubishi is green, just to name a few.

Which coolant is right for you? Many factors are involved and a close inspection on operations and clientele need to be taken into consideration. Many “lube centers”, or those that work on a variety of newer engines and cooling systems, have taken advantage of the versatility of a “global” HOAT coolant. This affords the luxury of stocking one antifreeze, which is compatible with many factory fill coolants. However if work tends to be on older cars, conventional “Green” technology will suffice. More make specific clientele should refer to the car’s owner’s manual.

How do I properly mix coolant if I buy full strength antifreeze?

There is no way of knowing whether or not you have the proper mixture by a simple visual inspection. A hydrometer can be used, which measures specific gravity by utilizing floats, to indicate freeze point. However, these are notoriously inaccurate. Over time, if these meters are not cleaned thoroughly after each use, the float becomes weighted, becoming less accurate. A refract meter measures light refraction to determine the amount of glycol. Refract meters are more accurate than hydrometers yet, more expensive. Properly measuring and mixing the water and antifreeze before adding them to the radiator is good practice.

What are the benefits of using pre-mixed antifreeze?

Water should normally be about half the fluid in your cooling system. Therefore, water quality is equally as important as the antifreeze you buy. Using tap water is never a good idea. Chlorine is added to purify tap water, but is aggressive towards aluminum, common in newer cooling systems. Tap water also is generally high in other contaminates such as magnesium and calcium. These can promote scaling which affects heat transfer the major cause of overheating. The worst potential enemy to your engine coolant could very well be the water that you use!

Sulfate, Magnesium and Calcium – The total concentration of these elements is called water hardness. These minerals form scale on hot heat exchange surfaces and are found in most city water.

Chlorine – All municipal water supplies contain chloride and chlorine. Chloride is very corrosive to all cooling system metals, especially aluminum!
Don’t waste good coolant with bad water!!! Using pure water, results in longer coolant life and more efficient heat transfer. Deionized or distilled water is ideal for mixing, but pre-diluted coolant is the best choice. This ensures quality and saves time and money by eliminating mixing mistakes.

I heard that cooling system failure is the most common cause of engine failure. Is that true?

Coolant neglect is cited as the principal reason for premature engine and transmission failure! Antifreeze/engine coolant is the most neglected fluid in the vehicle, and cooling system failure is the most common cause of mechanical breakdown on the road. Today, nearly all internal metal components of the cooling system are made of aluminum, which is susceptible to corrosion. Proper coolant with proper water is good insurance against the high cost of cooling system repairs.

Today’s engines run on the borderline of overheating. Newer engines, due to environmental issues, require cleaner burning engines. Engine manufacturers have raised engine operating temperatures in order to reduce exhaust emissions and improve fuel economy. This, however, creates unprecedented problems in the cooling system and amplifies past issues, such as scale.

Scale – Impedes heat transfer and causes localized hot spots, a major cause of engine overheating and component failure.

With costs of engine repairs easily reaching thousands of dollars, the most effective way to protect your investment, or your customer’s investment, is preventative maintenance.

What is the difference between Heavy Duty and Light Duty Coolants?

Light Duty Coolants are covered under ASTM D3306. This specification covers the requirements for ethylene glycol or propylene glycol base engine coolants used in automobiles or other light duty service cooling systems.

Heavy Duty/Fully Formulated Coolants are covered under ASTM D6210. This specification covers the requirements for fully-formulated glycol base coolants for cooling systems of heavy-duty engines.

The ASTM D6210 specification requires that antifreeze must protect wet sleeve liners without any initial addition of an SCA. This means formulating the liner protection into the antifreeze, hints the term “fully formulated”. Coolants usually contain nitrite or a combination of nitrite and molybdate to provide the liner protection.

I can buy Light Duty antifreeze cheaper at the parts store. Why should I pay more for Fully Formulated Coolant?

Light Duty Coolants offer little to no protection against liner pitting! Liner pitting occurs along the thrust angle of the piston. As the diesel engine works, combustion forces set up a natural vibration in the sleeves. Liners rapidly pull away from the coolant, creating a low-pressure area in which the surrounding coolant boils and forms tiny air bubbles. As the sleeve springs back, it slams into the bubbles with a force estimated at up to 60,000 psi, causing the bubbles to implode, violently. This action fatally attacks and bores through the liner, allowing coolant into the cylinder, where it will crack blocks, break pistons and bend rods. With costs of engine repairs easily reaching tens of thousands of dollars, the most effective way to protect your investment, or your customer’s investment, is preventative maintenance. Use only Fully Formulated Coolants as part of your service requirements! Be sure to pay close attention to service intervals, flushing and adding new coolant or adding the appropriate supplemental coolant additives as needed.

Should I use Ethylene or Propylene Glycol?

Propylene glycol and ethylene glycol are chemically similar; however propylene glycol is less toxic. Ethylene glycol has a slightly higher boiling point, more widely used and is less expensive to produce.

Is waste antifreeze dangerous to the environment?

Yes, waste antifreeze may contain contaminants such as lead, which can cause serious health and environmental problems. Antifreeze manufacturers also add a variety of chemicals to antifreeze to inhibit rust and corrosion, which also can endanger the environment. Large quantities of glycol can disrupt sewage treatment processes.

If I replace the antifreeze in an automobile with a S48R Antifreeze coolant (the automobile is under manufacturer warranty), will it void the warranty with regards to the cooling system?

As long as the coolant type is compatible with and equal to the chemistry used in your vehicle, it will not void the warranty.

Under the Magnuson-Moss Warranty Act (15 U.S.C. 2302) and general guidelines of the Federal Trade Commission, an original equipment manufacturer (OEM) may not make its vehicle warranty conditional on the use of any specific brand of motor oil, oil filter, antifreeze, or any other component unless the manufacturer provides it to the customer free of charge during the warranty period.

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