Ultra-low-sulfur diesel doesn’t provide sufficient lubricity

Ultra-low-sulfur diesel lacks Needed Lubricity

Mark Nyholm | TECHNICAL MANAGER, HEAVY DUTY AND MECHANICAL R&D

Fortunately, we have a simple solution.

It feels like forever ago, but it’s only been 13 years since the U.S. Environmental Protection Agency (EPA) mandated reduced sulfur content in diesel fuel, in 2006. Boy, were people angry. They knew sulfur helped protect their fuel pump and injectors from failure. Change is scary, and the thought of replacing expensive components even more so.

Fast-forward to 2019, and I rarely hear anyone talking about this. But the problem is even more prevalent now than it was then. Modern diesels demand even more from the fuel pump and injectors than before, increasing the potential for failure. So, why aren’t people still up in arms? My hunch is they have accepted the new reality. Or, they just don’t know what they don’t know when they buy a new truck today.

Today’s ultra-low-sulfur diesel fuel (ULSD) provides significantly reduced lubricity – a critical property in controlling fuel-pump and injector wear. While diesel fuel has traditionally had high lubrication properties, the desulfurization process used to strip the diesel fuel of the sulfur content to meet ULSD requirements also strips the fuel of some of its organic compounds responsible for lubrication. The ASTM D975 diesel-fuel standard mandates a minimum lubricity level. However, the Engine Manufacturers Association (EMA) wants the standard to provide for increased lubricity, but lost out on the control of the specification. While the EMA claims there’s a problem, it doesn’t carry enough clout to change the specification.

Since 2006, ULSD has accounted for nearly all diesel available in North America because the EPA mandated reduced sulfur to curb harmful emissions. ULSD now contains a maximum of just 15 ppm sulfur, compared to fuel that had up to 5,000 ppm sulfur prior to EPA regulations.

Waxes in diesel fuel lubricate the fuel pump and injectors, helping fight wear. Without them, the highly engineered components in modern diesels, particularly high-pressure common rail (HPCR) engines, can wear out and cost thousands in repairs. They can also develop deposits that interfere with an optimum spray pattern, reducing power and fuel economy. The editors of Diesel Power Magazine covered the problem of ULSD in the April and May 2019 issues. As reported, the Bosch* CP4.2 fuel pump that comes stock on 2011-2016 Duramax* engines has led to thousands of catastrophic failures. It’s culminated in class-action lawsuits in Texas and California against Bosch, GM*, Ford* and other vehicle manufacturers on behalf of individual diesel owners whose vehicles use that pump. When the CP4.2 fuel pump fails, it instantly contaminates the entire fuel system with metal particulates, costing $8,000 to $12,000 in repairs. The magazine reiterates what AMSOIL has been saying for years: “The way to be proactive in protecting a CP4.2 equipped diesel from an early demise is being diligent about using fuel additives that add lubricity with every fill-up.”

The CP4.2 pump is said to fail because of two reasons: 1) It’s designed with about 20 percent reduced flow volume than the previous generation pump, requiring it to work even harder. 2) ULSD isn’t providing enough lubricity.

Our testing of base fuels across the U.S. confirms the second point. ASTM D975 requires diesel fuel to limit the wear scar in lubricity testing to 520 microns. The EMA, meanwhile, sets its own, stricter requirement of 460 microns. As the chart shows, many of the fuels (blue bars) failed to limit wear to 520 microns. And none of them met the EMA’s 460-micron limit.

Fuel treated with AMSOIL Diesel All In-One (ADB) performed far better (red bars). It not only met the ASTM D975 standard, it also met the stricter EMA lubricity requirement. You can find the same technology in Diesel Injector Clean (ADF) and Diesel Injector Clean + Cetane Boost (ADS). Our diesel additives deliver a healthy boost in lubricity to help lubricate diesel fuel pumps and injectors. The extra lubrication helps prevent wear in fuel pumps and injectors. I strongly recommend that all diesel owners use AMSOIL diesel fuel additives with every tank of fuel.

We keep this in large supply in Sioux Falls – Both our Stan Houston’s location and the Tea Exit location (exit 73). Buy in the half gallons to save money.

Motorcycle Oil, Primary Fluid & Transmission Fluid: What’s The Difference?

The Fool Said I Can Use 20W-50 In All Three. What?

Some V-twin motorcycles, like modern Indian and Victory bikes, use a shared sump, meaning they use the same lubricant in the engine, transmission and primary chaincase. Most Harley Davidson motorcycles, however, use a separate sump for each lubricant. This presents Harley (Don’t forget about Davidson) owners with a choice: Use the same lubricant in all three areas of the bike, or use a separate lubricant formulated and labeled for each area. Here, we offer guidance for deciding what’s right

For the record, AMSOIL recommends AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil (MCV) in the engine, transmission and primary chaincase on most Harleys (consult the Motorcycle Product Guide at amsoil.com for specific recommendations). It offers…

Convenience. Riders buy and install one lubricant. This reduces cost and results in fewer half-used bottles of oil lying around the garage.
Simplicity. Remembering to buy one lubricant is far easier than remembering three.
Great all-around performance in all three areas of the bike.
It’s what the upper brass at AMSOIL use in their bikes.

We formulate 20W-50 Synthetic V-Twin Motorcycle Oil to be an excellent all around lubricant. It delivers outstanding engine protection due to its proven ability to fight wear, reduce heat, maintain cleanliness and prevent corrosion during storage.

See why the 50 weight qualifies as a 90 in the transmission.

Synthetic V-Twin Motorcycle Oil also boasts a shear-stable formulation. It resists viscosity loss despite the intense pressure and churning action of high RPM transmission gears, allowing it to deliver reliable transmission protection. Synthetic V-Twin Motorcycle Oil meets JASO MA/MA2 standards and is wet-clutch compatible for excellent performance in the primary chaincase. Its frictional properties are dialed-in to allow the clutch plates to engage and disengage without loading or slipping for smooth shifts.

Despite these benefits, some riders question the practice of using one lubricant in all three areas of their bikes. They have a difficult time accepting that a motor oil can also protect the transmission and primary chaincase.

I don’t think so. My Mechanic always said you have to use different oils. – That’s partially true…

If you believe this to not be true we make the separates for you. Debate free oil options! And yes, they are more dialed in.. This is why we offer Synthetic V-Twin Transmission Fluid (MVT) and Synthetic V-Twin Primary Fluid (MVP).

What are the differences?

In essence, Synthetic V-Twin Transmission Fluid and Synthetic V-Twin Primary Fluid are formulated to protect just one area of your bike rather than three. This specificity allows us to engineer each lubricant for its precise application.

Transmission Fluid

Synthetic V-Twin Transmission Fluid has a higher viscosity than 20W-50 Synthetic V-Twin Motorcycle Oil. A higher-viscosity, or “thicker,” lubricant can help quiet noisy transmission gears and enable smooth shifts. The lubricant develops a slightly thicker fluid film on gears, which provides cushion to help diminish loud “thunks” and gear noise.

Again, we realize that’s what people want and in some cases it’s beneficial to the gears but it’s slightly thicker than the OEM specifications or better put – on the high side of the range. The only real downside other than cost is less efficiency in cooler weather and a change in overall MPG.

Primary Fluid

Likewise, AMSOIL Synthetic V-Twin Primary Fluid is designed only to protect primary chaincase components. Its viscosity is similar to an SAE 50 motor oil. Formulating it as a straight-weight lubricant naturally offers an advantage in shear stability over other multi-viscosity lubricants. (AMSOIL 20W-50 Synthetic V-Twin Motorcycle Oil is absolutely shear stable and will not thin out from mechanical activity.) This helps the fluid remain thicker, which helps it cling to the compensator without being “flung off” as easily for maximum protection. In Harleys, the compensator acts as a shock absorber to prevent engine vibration from affecting the transmission. Compensator wear often leads to a knocking or ticking noise.

Synthetic V-Twin Primary Fluid also clings well to the chain for excellent wear protection. And its wet-clutch-compatible formulation meets JASO MA/MA2 requirements.

Many buy this because some bikes have issues shifting back to neutral. AMSOIL Primary Oil makes it much easier for the linkage to catch neutral when you need it.

One oil or three?

So, which is the better route for Harley owners? Either way you can’t go wrong but examine if you identify with the issues requiring the 2nd choices.

For riders who desire the simplicity and convenience of using one lubricant for all three areas, following our primary recommendation of 20W-50 Synthetic V-Twin Motorcycle Oil in all three areas is the best choice.

For riders who prefer lubricants dialed in for each area of their bikes and don’t mind a few extra bottles of oil lying around the garage, steer them toward our full line of V-twin lubricants.

Either way, they can’t go wrong.

Ordering 605-274-2580

Tag: amsoil