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Why is there this hard to Flush Slime in my Radiator?

Why is there Sludge or Slime in my Radiator?

Cooling-system issues account for nearly 40 percent of engine failures. Clearly, it pays to take care of your vehicle’s cooling system.

Sludge/slime are one of the common symptoms of larger problems. Left unchecked, it’ll plug the radiator, heater core or fluid passages, resulting in overheating and expensive repairs.

What causes sludge/slime and what can you do about it?

• Additives dropping out – coolant consists of a base (typically ethylene glycol or propylene glycol) mixed with additives and water. The base is primarily responsible for providing freeze and boil-over protection. The additives guard against corrosion, cavitation and scaling. Mixing of incompatible coolants can cause the additives to “drop out” of the solution and form sludge or slime.

• Contaminated coolant – a bad head gasket or cracked cylinder head can allow oil and coolant to mix, resulting in sludge. In vehicles with automatic transmissions, the engine-cooling system also cools the transmission. A breach in the system can contaminate coolant with transmission fluid.

• Corrosion – occurs when an imbalanced coolant chemically reacts with metallic surfaces, forming reddish deposits that can appear as sludge or slime.

Low-quality coolants can lead to cooling-system corrosion.

The only way to definitively identify what’s causing sludge/slime in your radiator is to perform fluid analysis. The report can identify oil, transmission fluid or other contaminants in the coolant. Fix any mechanical defects and flush the cooling system. Refill with a high-quality antifreeze/coolant.

What kind of coolant should I use?

Let’s start with what kind you should avoid.

You’re no doubt familiar with the conventional “green” coolants found at most retailers due to their low price. They contain inorganic salts, such as nitrites, phosphates and silicates.

Inorganic salts deplete quickly – typically in two years or less – and are on the environmental watch list. Once depleted, they are the source of common cooling-system problems, like scale deposits and sludge/slime.

Low-cost “green” coolants are the source of several problems, such as sludge/slime and scale deposits.

For these reasons, most vehicle manufacturers have moved away from inorganic salts for newer vehicles.

And so should you.

Instead, use a high-quality coolant that uses organic-acid technology (known as OATs). OATS coolants are much more robust and longer-lasting. They virtually eliminate drop-out, scaling and compatibility issues inherent to inorganic salts. This type of coolant can be used in a wide variety of applications, even mixing with other coolants as a top-off.

AMSOIL Antifreeze/Coolants

AMSOIL offers three coolants, all of which offer a unique blend of organic acids. We use di-acid technology, which means both ends of the organic acid are active. This makes them work faster and form stronger bonds for enhanced protection.

How Does a Dual-Clutch Transmission (DCT) Work?

The Function of a Dual-Clutch Transmission

Market Technology before it’s ready!

A dual-clutch transmission (DCT) is synonymous with high performance. Compared to a traditional automatic transmission, it delivers…

  • Faster, smoother shifts
  • Increased fuel economy
  • Improved performance
  • Surprise breakdowns (well they’ll solve that soon)

Although the DCT transmission dates to the 1930s, it made its first practical appearance decades later in several 1980s-era race cars.

In 2003, the Volkswagen Golf Mk4 R32 was the first production vehicle to feature the technology.

Today you can find a DCT in a variety of cars, from the relatively tame Hyundai Sonata to the brash, sexy Nissan GT-R.

How a DCT transmission works

DCTs are essentially two manual transmissions working in tandem.

One gear shaft contains the even-numbered gears, and the other contains the odd-numbered gears. While you’re accelerating in first gear, for example, the computer selects second gear on the other gear shaft. When it’s time to up-shift, the clutch that controls the even gears disengages and the clutch that controls the odd gears engages.

Compared to a traditional automatic transmission, gears shift much more quickly and smoothly in a DCT transmission – the perfect complement to a powerful, high-performance engine.

While DCTs are capable of seamless shifts, they can suffer from shudder or lurching at slow speeds.

Transmission fluid with specific frictional properties is required to prevent shudder. DCT fluid must also maintain the proper viscosity to provide protection during the high-heat operation native to high-performance sports sedans and supercars.

100% Synthetic Dual-clutch Transmission Fluid (DTC)

Protect the thrill

AMSOIL 100% Synthetic DCT Fluid is specifically engineered for sophisticated dual-clutch transmissions.

Its superior frictional properties protect against shudder and gear clashing to consistently produce fast, smooth shifts. When you are waiting on the light you need a fluid engineered to solve the “constant slip mode” which is occurring to work as if it had a torque converter. Slight engagement while you are on the brakes requires beyond expectations technology you only can expect from AMSOIL.

AMSOIL Synthetic DCT Fluid’s exceptional durability provides stability in stop-and-go traffic and excels under intense, high-heat conditions. Its built-in oxidation resistance helps prevent sludge formation in vital transmission parts.

Available in our 98th St store. Just behind the Marlins at the Tea exit. Exit 73 Sioux Falls.

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