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Want the Best Diesel Oils for Your Vehicle?

Confused About Diesel Oil? We’ll help you

Your diesel truck is a serious investment – don’t skimp on protection. AMSOIL manufactures the best diesel oils on the market, providing the ultimate protection for your hard-working diesel engine, preserving the horsepower you crave and keeping you on the road.

We engineer our synthetic diesel oils with the same passion and pride you put into your turbodiesel, providing protection you can depend on in the most severe operating conditions.

Do you want extra engine protection?

Excessive wear to diesel cylinder liners and rings leads to increased oil consumption and loss of compression, reducing horsepower and fuel economy.

AMSOIL delivers rock-solid wear protection you can rely on.

Do you tow or haul?

Operating at up to 150,000 rpm in temperatures that exceed 1,000°F (538ºC), a turbocharger on a stock engine can dish out a lot of punishment to your oil.

If it’s not formulated to take the beating, the oil can break down, creating deposits and wear.

For some, stock engines don’t provide enough power, but dropping a tune on your engine puts even more stress on both your turbo and your oil.

Here again, AMSOIL delivers.

When you push the Turbo in your diesel, we'll provide the extra protection.

Do you store your vehicles and equipment?

Intermittent use, prolonged storage, humidity and short drives can lead to the development of rust and corrosion, causing major damage to diesel engines.

Come of the better known diesel oils offer little rust protection if any.

Do you drive in hot temperatures?

AMSOIL synthetic diesel oils resist thermal (heat) breakdown better than conventional and competing synthetic diesel oils, effectively retaining their protective viscosities for added engine protection in extreme temperature conditions.

Check out the entire AMSOIL diesel Oil line

Do you drive in cold temperatures?

Unlike conventional oils, AMSOIL synthetic diesel oils contain no wax, staying fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear.

Signature Series 0W-40 has a broad viscosity range that offers 4X better cold-cranking ability than a 15W-40. Use the 0W-40 year round here in Sioux Falls  – no problem!

Find out how to keep diesel fuel from gelling in the cold.

Do you own a high-mileage vehicle?

AMSOIL synthetic diesel oils provide low rates of volatility (burn-off), reducing oil consumption during operation and passing less oil vapor into the combustion chamber.For example the Signature Series in 2017 and earlier Duramax engines per customer feedback yield a significant reduction in regens! The savings in fuel and agony is worth that alone.

Reduced oil consumption is especially important for the performance of your exhaust system.

lower oil consumption saves you in future diesel downtime and loss of fuel economy.
A top seller in the Sioux Falls 98th St Store.

 

Low-viscosity doesn’t mean low quality

Low-viscosity doesn’t mean low quality

As motor oil viscosity continues to decrease, base oil and additive quality become more important.

Michael Meuli | VICE PRESIDENT, TECHNICAL DEVELOPMENT

Despite uncertainty surrounding future CAFÉ standards, fuel economy remains the biggest driver of innovation in the auto industry. One strategy for increasing fuel economy involves reducing energy lost to friction. Using lower-viscosity lubricants, which reduce pumping losses and flow easier at startup, helps automakers accomplish this goal. Just as we’ve become accustomed to 0W-20 oils, 0W-16 oil has entered the market and is recommended for the 2018 Toyota Camry and Honda Fit. People are wondering how much lower viscosity can go.

That’s because excessively low lubricant viscosity can reduce wear protection. Some people fear the fuel economy gains of modern low-viscosity oils aren’t worth the potential loss of wear protection. You should be familiar with the relationship between lubricant viscosity and wear protection, but it bears repeating.

Motor oil must develop a durable fluid film that separates engine components so they don’t rub together and wear out. As a rule of thumb, the higher the oil’s viscosity, the thicker the fluid film – and the better the wear protection.

That being the case, you might think it advantageous to throw out your 0W-20 motor oil and use 15W-50 instead. That’s a bad idea, and here’s why.

Modern engines are built with tighter clearances between parts than their predecessors. Let’s take the GM* 3.8L engines we test in our mechanical lab as an example. The clearances between the crankshaft journals and main bearings can be as low as .0007 inches. That’s thinner than a sheet of paper (about .004 inches).

During operation, oil continuously flows through tiny ports in the crankshaft journals to lubricate the journal/ bearing interfaces. It should form a strong, consistent oil film on which the crankshaft journals float as they spin, preventing them from touching the bearings. This is called hydrodynamic lubrication. Oil that’s too thick for the engine, however, may not flow fast enough to fill the clearances, allowing the high spots on metal surfaces to contact. This is called boundary lubrication.

In this case, using a higher viscosity oil than what’s recommended in your modern engine would lead to increased wear. Adding insult to injury, it would reduce fuel economy and increase operating temperatures as well.

Viscosity that’s too low, however, can have the opposite effect. Since viscosity is related to film thickness, low-viscosity oil may not develop an adequate fluid film to keep metal components separated, leading to wear. If bad enough, parts will eventually weld together and destroy the engine.

You can see how modern engines have put oil formulators into a bind. How do we formulate low-viscosity oils that maximize fuel economy while also providing good wear protection in today’s stressful engines?

In a word, quality.

Although oil film thickness is related to lubricant viscosity, film strength is a function of base oil and additive quality. We start with high-quality synthetic base oils that offer naturally high resistance to heat and chemical breakdown.

The challenge, however, is that lower viscosity oils tend to be more volatile, meaning they burn off more easily when exposed to high heat. If you ever look at a motor oil’s NOACK Volatility, you’ll notice volatility tends to increase as the oil viscosity decreases. This is of particular importance since most new vehicles are equipped with turbocharged engines, which generate increased heat. High volatility can lead to excessive oil consumption, which causes the oil to thicken, making it harder to pump through the engine and reducing fuel economy. Oil that has thickened can also lead to deposits and disrupt the additive balance.

That’s why only synthetic base oils can be used to formulate a 0W-16 motor oil. Conventional base oils are too volatile to meet requirements of low-viscosity oil.

Additives, too, play a vital role in low viscosity oils. We talked about boundary lubrication earlier. When in a boundary lubrication situation, protecting against metal-to-metal contact falls on the motor oil’s anti-wear additives, more so than with higher viscosity oils. The additives form a sacrificial barrier on metal parts that absorbs contact and protects the metal surfaces.

Motor oil quality has always been important, but modern low-viscosity oils underscore the point. That’s good news for Dealers selling the best oil on the market.

To help you reach this market, we introduced new OE 0W-16 Synthetic Motor Oil (OES) last month. We’ll monitor demand for 0W-16 oils and introduce additional formulations if demand dictates.

In the meantime, brace yourself for 0W-8 motor oil, which is already being tested in Japan.

Help! How Many Quarts of Oil Does My Car Use?

How Much Oil Does My Car Need?

The answer seems simple: probably about five quarts.

But, if you drive a small car with a four cylinder engine, it’s likely closer to four quarts. However, the V-8 engine in your truck could require about seven quarts. My in-laws’ RAM diesel pickup takes 12 quarts of motor oil.

You can see how the answer isn’t so simple after all.

To find out precisely how much motor oil your car needs, do one of the following:

  1. Check the owner’s manual

Dig the owner’s manual out of your glovebox and look up the information in the index. Eventually you’ll find it.

  1. Check the AMSOIL Product Guide

You can skip the hassle and use our Product Guide instead. Just input your vehicle information and, below the motor oil recommendations, you’ll find motor oil capacity (circled below in red).

What if the oil level is too low?

It could be due to a couple issues, including insufficient oil added during the last oil change or oil consumption. There are several reasons for oil consumption (in fact, you can read about 40 of them here). But here are a couple of the more common.

Leaking seals or gaskets – your engine uses seals in various places to ensure oil stays inside the engine while contaminants stay out. A prime example is around the crankshaft where it sticks out of the engine and connects to the transmission. Gaskets seal the uneven metal surfaces between parts to ensure, in part, that oil stays inside the engine. The cylinder head gasket is a notable example.

If the seals and gaskets become worn, brittle or deformed over time, they can result in oil leaks. The engine oil level will drop, depending on the severity of the leak. If your engine leaks oil, visit a mechanic and have it fixed.

Volatility – engine oil can evaporate when exposed to heat. The less stable the oil, the more readily it evaporates. As the engine is running, a thin film of oil coats the cylinder wall and piston skirt. Given its proximity to the fiery cauldron inside the combustion chamber, the oil in this area of the engine can easily volatilize, or evaporate. The by-products can exit the tailpipe as emissions. But they can also form harmful carbon deposits inside the engine that reduce efficiency and eventually lead to engine failure.

Synthetic motor oil is more resistant to volatility than conventional oil, so use a good synthetic to reduce oil consumption due to volatility and help keep your engine clean.

What if the oil level is too high?

It’s likely due to operator error; someone simply added too much last time the oil was changed or topped-off.

Too much oil is a bad thing. The spinning crankshaft and churning engine parts whip air into the oil, which can cause foam. The tiny bubbles travel between moving parts, where they rupture. When they do, nothing is left to protect metal surfaces from wear. Foam also increases heat, which causes the oil to chemically breakdown sooner.

If the crankcase is overfull, drain the excess oil until reaching the correct level.

Increased oil level can also be due to fuel dilution. This is when fuel enters the crankcase and contaminates the oil. In severe cases, enough fuel can enter the crankcase to noticeably increase the oil level. This is bad. Very bad. Fuel dilution leads to sludge, varnish and engine wear.

Check out this post for more on fuel dilution.

The presence of coolant in the oil can also increase oil level. Again, this is bad. Anytime something that shouldn’t be in your motor oil is present, wear protection suffers. Coolant in the oil is likely due to a bad head gasket, which is a costly repair.

One last word of advice: check your oil at least monthly to ensure the proper level. Make sure the vehicle is parked on a level surface to get an accurate reading. Finding out the oil is too low or too high before something goes wrong can save you a ton of grief in the long run.