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409,000-Miles Without An Oil Change

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AMSOIL Series 3000 Synthetic 5W-30 Heavy Duty Diesel Oil is Correct Choice for Jeff Foster Trucking

AMSOIL Products Improve Efficiency and Reduce Operating Costs for Gerlach Trucking

What is the Noack Volatility Test?

What is the Four-Ball Wear Test?

What is TBN?


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ZDDP Zinc Dialkyldithiophosphate Provides Proven Wear Protection

But Its Incompatibility With Pollution-Reduction Devices Severely Limits Its Use in Modern Motor Oils.

Dan Peterson, Vice President, AMSOIL Technical Development

Dan Peterson
Vice President,
Technical Development

As today's automotive engines push the envelope seeking higher fuel economy and lower emissions, the demands placed on motor oil are escalating. This push for improved performance is nothing new. Racers and muscle-car owners have long looked for ways to squeeze more horsepower from their vehicles. This is often done in vintage cars by modifying the engine, while tuner enthusiasts usually focus on computer-controlled performance improvements. Whatever your preferred method, it puts more stress on engine components, and the oil must protect parts from wear even as they are pushed beyond the limits of OEM design. This is where the most recognized anti-wear additive, zinc dialkyldithiophosphate (ZDDP), comes into the picture.

ZDDP is very good at reducing wear and improving oxidation stability. It also exhibits mild extreme-pressure (EP) protection. ZDDP contains both zinc and phosphorus components that work together to provide anti-wear protection and minimize lubricant breakdown. Specifically, ZDDP helps protect high-impact surfaces like camshaft lobes, lifter surfaces and rockers against wear. As temperatures rise and surfaces come closer together, ZDDP decomposes and the resulting chemistry is what protects the critical metal surfaces. When parts move during operation, any sliding or rolling motion takes place on top of or within the ZDDP anti-wear film, which reduces metal-to-metal contact. This is especially important in modified engines with flat-tappet camshafts because the engine is creating more horsepower than it was designed for, which puts more stress on the engine. The camshaft and lifters are responsible for triggering the precisely tuned movements of the valvetrain. Without the protective film barrier provided by ZDDP, the cams and lifters will wear from the force of operation, resulting in poor performance. All engines benefit from oils with superior film strength and anti-wear properties, so why don't all motor oils have boosted levels of ZDDP? It's back to the goal of improving emissions systems performance. Generally, ZDDP used in high levels results in volatile phosphorus being transferred from the combustion chamber to the catalytic converter. Like with lead in 1970s gasoline, phosphorus can blind over the catalytic reaction sites in the converter, making it less efficient in turning carbon monoxide (CO) into carbon dioxide (CO2). The EPA mandates that catalytic converters operate as designed for more than 100,000 miles. As a result, ZDDP levels are now limited for newer motor oil specifications. The largest portion of the volatile phosphorus is generated right after you change your oil. So the more you change your oil, the more your catalytic converter is exposed to this volatile phosphorus. Conversely, longer drain intervals can limit the negative impact of volatile phosphorus on catalytic converters.

Both engine technology and oil technology have evolved over the years. Today's performance engines have very different oil requirements compared to older engine designs from the 1960s and 1970s. Many new engines use roller cams, which aren't as sensitive to ZDDP anti-wear protection as older flat-tappet camshafts and solid lifters. Older engines equipped with flat-tappet cams require higher levels of anti-wear/ mild EP (ZDDP) than today's engines. This area in an engine is exposed to extreme contact load. Since this load increases significantly when non-stock, high-pressure valve springs are used, the use of properly formulated motor oils is extremely important to reduce wear and extend flat-tappet and camshaft life, especially during the critical break-in period. Since the amount of zinc and phosphorus in oils formulated for today's automobiles has been greatly reduced and newer API oils are not designed specifically for older-style, modified engines, engine wear can be a major issue.

AMSOIL manufactures a complete line of motor oils tailored to meet the specific needs of classic cars and other vehicles requiring higher anti-wear/mild EP protection. AMSOIL Z-ROD® Synthetic Motor Oil (ZRT, ZRF) is designed with the level of anti-wear/ mild EP required to safely protect older and modified engine designs such as those with flat-tappet camshafts. It is also designed specifically to resist rust and corrosion that attacks engines
during periods of inactivity and storage. AMSOIL DOMINATOR® Synthetic Motor Oil (RD20, RD30, RD50, RD60) is formulated similarly, but more for true racing applications. This makes it the right choice for muscle cars, street rods and other high-performance vehicles with flat-tappet camshafts. AMSOIL Break-In Oil (BRK) is designed to work quickly in new and rebuilt high-performance and racing engines. This SAE 30 viscosity grade oil features a no-friction-modifier formula that helps induce controlled wear in rings to help mate and seat piston rings. It also has very high levels of ZDDP.

Whether you're a classic-car enthusiast, hot rodder, tuner or drifter, your equipment may require the protection provided by these products. Knowledge is power; but we want you to experience maximum power from your engine also! Published, AMSOIL Magazine 12/13.

AMSOIL Signature Series Synthetic Motor Oil

AMSOIL Signature Series Synthetic Motor Oil

AMSOIL Signature Series Synthetic Motor Oils are formulated to meet the latest API SN Resource Conserving and ILSAC GF-5 industry specifications. AMSOIL Signature Series Oils include 0W-20, 0W-30, 5W-30 and 10W-30 and represent the very best motor oils AMSOIL has to offer, allowing motorists to take advantage of maximum extended drain intervals. AMSOIL Signature Series Synthetic Motor Oils are recommended for drain intervals of up to 25,000 miles/one year, whichever comes first (15,000 miles/one year in severe service conditions).

Click here for more information

Premium AMSOIL Synthetic Motor Oils offer the longest drain intervals on the market, unsurpassed protection and performance that effectively extends equipment life and improved fuel economy, saving customers money at the pump and reducing the nation's dependence on foreign oil.



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AMSOIL Synthetic Diesel Oil Articles and Testimonials

"AMSOIL INC. warrants that the use of its lubricants will not cause mechanical damage to any mechanically sound equipment when AMSOIL INC. products are used in full compliance with the company's recommendations and instructions."


AMSOIL synthetic motor oils are formulated to surpass engine test specifications, offering protection far greater than competing motor oils for extended drain intervals. Most synthetic oil manufacturers make no claim to extended drain intervals, deferring to the maintenance schedule provided by the vehicle manufacturer. With its unparalleled oil and warranty program, AMSOIL offers consumers unprecedented protection and economics.

Another AMSOIL First

More than 20 years ago, AMSOIL began using the NOACK volatility test as a comparison tool and measurement of quality. Back then, nearly every oil tested side-by-side with AMSOIL synthetic motor oils failed, and those that passed barely squeaked by. Other oil companies paid no attention to NOACK results until Ford Motor Company made it a requirement for service fill oils, validating what AMSOIL had said all along.

THE NOACK Volatility Test
The NOACK Volatility Test determines the evaporation loss of lubricants in high temperature service. The more motor oils vaporize, the thicker and heavier they become, contributing to poor circulation, reduced fuel economy and increased oil consumption, wear and emissions. AMSOIL Synthetic Motor Oil resists high temperature volatization better than other motor oils. AMSOIL Synthetic Motor Oil maintains peak fuel efficiency and reduces oil consumption and emissions.

AMSOIL Now An ISO Certified Manufacturer
AMSOIL recently received ISO 9001:2000 certification of our Quality Management System (QMS). NSF International Strategic Registrations is the registrar that has verified our QMS meets the requirements of the ISO 9001:2000 standard, the most widely utilized quality standard throughout the world for quality management systems. ISO standards are used by over 300,000 companies worldwide setting rigorous standards for businesses, government and industry.

ISO 9001:2000 is applicable to any manufacturing and service organization providing a framework for system development that focuses on the customer, quality system performance and ongoing improvement. AMSOIL received ISO 9001:2000 registration under the scope: synthetic lubricants blending, packaging, and other fulfillment directly associated with lubricant product.

The ISO certification puts AMSOIL in line with some of the most efficient companies in the world. It is further assurance that the products and services AMSOIL provides will continue to maintain the high level of quality the company always demanded.

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