A Closer Look at the New AMSOIL Synthetic Diesel Oil Lineup

An Interview with Alan Amatuzio

New Signature Series Max-Duty Synthetic Diesel Oil and Heavy-Duty Synthetic Diesel Oil represent a leap forward for diesel engine protection and performance. We sat down with AMSOIL Co-President & COO Alan Amatuzio to learn what this means for customers.

AMSOIL Magazine: The new Signature Series Max-Duty Synthetic Diesel Oil lineup has replaced Premium Synthetic Diesel Oil, while the new Heavy-Duty Synthetic Diesel Oil lineup has replaced OE Synthetic Diesel Oil. These new oils were developed to meet the latest API CK-4 specification, correct?

Amatuzio: Yes, the new API CK-4 specification represents a true upgrade in performance. We have fully embraced it, and feel strongly about its ability to protect modern diesel engines. When its predecessor, CJ-4, was introduced a decade ago, we were apprehensive. There was a takeaway in sulfated ash content (TBN) that we didn’t think adequately addressed the latest engine hardware changes. The new CK-4 standard, however, represents a real improvement, and oils meeting the CK-4 standard are better-equipped to protect modern diesel engines.


AMSOIL Magazine: Why did AMSOIL introduce two different diesel oils: Signature Series and Heavy-Duty?

Amatuzio: We did a lot of market research and put a lot of work into understanding our customers and what they want. With that knowledge, we developed two distinct lines to fulfill the variety of customer needs and wants. We developed Signature Series for customers who want nothing but the very best protection for their vehicles and equipment, and we developed Heavy-Duty for price-conscious customers and customers who are not interested in the benefits of extended drain intervals, but still want outstanding protection for their vehicles and equipment.


AMSOIL Magazine: Is this why both diesel oil lineups include a 5W-40 viscosity – to provide options within the same market?

Amatuzio: Absolutely, 5W-40 is the primary recommendation for turbodiesel trucks, and it’s important to have products for this market. Different customers have different buying motivations, and offering both Signature Series 5W-40 and Heavy-Duty 5W-40 presents options. Signature Series also has wider applicability, appealing to over-the-road truckers who want a great combination of wear protection and fuel economy, as well as the convenience and cost savings of extended drain intervals.


AMSOIL Magazine: Why was the Signature Series brand carried over into the diesel world?

Amatuzio: Oil chemistry and additives have come a long way since the introduction of the API CJ-4 specification, and the advanced technology we used to formulate Signature Series is worthy of the Signature Series name. We don’t use this name with every product. To be worthy of our founder’s signature, the product must represent the pinnacle of technology. The new Signature Series Max-Duty Synthetic Diesel Oil does just that. It’s an unapologetic, top-tier product geared for those who want the absolute best. It incorporates the top-of-the-line technology our competitors won’t touch because it’s too costly.

Some might say Signature Series is too good or it’s overkill, but we say overkill is underrated. Our customers rely on their vehicles and equipment to make a living; turbodiesel enthusiasts are passionate about their vehicles and invest a lot of money into them. They want the best protection money can buy. Signature Series provides it.

It’s a special product that we’re very proud of. It provides 6X more protection against cylinder wear than required by a leading industry standard*. Cylinder wear leads to oil consumption. Wear protection and reduced oil consumption are the top benefits our customers told us they want in a diesel oil. Signature Series hits it out of the park when it comes to addressing these issues.


AMSOIL Magazine: How does Heavy-Duty Synthetic Diesel Oil stack up?

Amatuzio: Heavy-Duty Synthetic Diesel Oil is geared for price-conscious customers, but when it comes to protection, it’s an outstanding option. It presents a serious upgrade over conventional and competing synthetic diesel oils, providing 4X more engine protection than required by a leading industry standard*, which, again, reduces oil consumption.

While Signature Series may be used for extended drain intervals, Heavy-Duty Synthetic Diesel Oil is recommended for OEM-specified drain intervals. Not everyone wants to extend their drain intervals, and that’s fine. Here’s a cost-competitive product that provides wear protection well beyond what can be found elsewhere.


AMSOIL Magazine: While the old OE Synthetic Diesel Oil was API-licensed, Heavy-Duty Synthetic Diesel Oil is not. What led to this decision?

Amatuzio: The API licensing system is a voluntary certification that only sets minimum quality standards. We examined the licensable API CK-4 technology on the market, and it did not meet our standards. Tying ourselves to an API license also limits the flexibility we need to quickly adopt new technologies that can further improve protection.

Before making the important decision on whether to seek the API license or not, we performed an extensive survey of our customers to determine which was more important to them: the API license or better protection and performance. The message was clear: Our customers look to us to provide outstanding protection and performance, and this is what is most important to them.

When formulating our new diesel oils, we used the API CK-4 specification as the minimum and engineered protection that surpasses it. We want to give customers the most protection we can, and sometimes that requires opting out of a licensing program. Diesel customers can rest assured their equipment is protected, and we back them up with our warranty.


AMSOIL Magazine: Why doesn’t Signature Series 0W-40 carry the 6X more wear protection claim that’s common to the other Signature Series viscosities?

Amatuzio: Although Signature Series 0W-40 uses the same advanced synthetic chemistry as the rest of our Signature Series line, the 6X more wear protection claim is based on the Detroit Diesel DFS 93K222 specification, which doesn’t recognize the 0W-40 viscosity. However, because cold-temperature performance is the primary attribute in which customers buying 0W-40 are interested, we’re marketing this oil with a very impressive claim: Signature Series 0W-40 offers 4X better cold-temperature performance**. That means engines turn over faster in cold weather, while start-up wear and unnecessary idle times are dramatically reduced, helping extend equipment life.


AMSOIL Magazine: I’ve heard Signature Series incorporates new additive technology. What are the benefits?

Amatuzio: Yes, we formulated Signature Series with a highly advanced mixed detergent system. Its magnesium and calcium content provides strong TBN retention, which makes it better at fighting acids and keeping engines clean. While other diesel oils may start with a high TBN number out of the bottle, the key is how well the oil retains alkalinity throughout its service life. This relates to what is known in the industry as hard TBN and soft TBN. Hard TBN effectively neutralizes acids and is achieved with the proper balance of calcium and magnesium additives. Soft TBN helps fresh oil achieve a high TBN number, but it depletes rapidly and is ineffective at neutralizing acids. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil boasts 10 points of hard TBN, acid-neutralizing power that effectively protects engines for the long haul.


AMSOIL Magazine: Diesel engines are an expensive investment. While our new diesel oils provide second-to-none protection and performance, is there anything else diesel owners can do to protect and extend the life of their equipment?

Amatuzio: Yes, pairing an AMSOIL Ea® Bypass Filtration System with our top-tier diesel oil presents a serious 1-2 punch against wear. No matter how good the oil, particles present a serious challenge to equipment life. It is up to the oil to protect against metal-to-metal contact, deposits and acids, but it can’t protect against invasive particles. It is the filter’s job to remove particles from the system, but most full-flow filters are only effective removing particles down to 20 microns in size. AMSOIL Ea Bypass Filters efficiently remove contaminants down to 2 microns, dramatically reducing long-term wear. Not only that, but adding an Ea Bypass Filter allows the user to increase oil capacity. The more oil in the system, the more protection against wear.

*than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222.

**when compared to SAE 15W-40 in ASTM D5293 Cold-Cranking Viscosity test.

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