Protecting Our Freshly Built Duramax With A Full Amsoil Fluid Swap

There’s nothing finer than the joys of finally finishing a full vehicle build. The long days, anxious nights, tears, heartbreak, blood, and sweet have all led to this moment. The joy of finally heading out into the world is euphoric. What if we told you that at that point the work isn’t completely done. Even if you’ve used the best parts and premium fluids, such as those from Amsoil, there’s still more to be done.

Whenever anything that relies on a fluid is rebuilt there’s a risk of contamination. Machining debris, casting sand, and loose metals or fibers can all break free in the first few miles. For this reason, it is critically important to go back and change the fluids as soon as the prescribed break-in period is complete.

For us this meant a full fluid change just 2,000 miles after completing the build of our 2002 Chevy Silverado 2500HD. This truck saw a full engine build along with the transmission, transfer case, and differentials. Knowing that Amsoil is a one-stop-shop for all things automotive fluid we hit the company’s catalog and ordered up a full complement of lubricants.

How Was Amsoil Founded?

Albert J. Amatuzio was a jet fighter squadron commander in the U.S. Air Force. Amatuzio noticed that the synthetic lubricants used in jet engines provided greater performance than conventional fluids along with superior protection in extreme temperatures and longer service intervals. This led him to experiment with synthetic lubricants for automotive use in the early 1960s.

In 1972 Amsoil 10W-40 became the first synthetic engine oil to meet the American Petroleum Institute (API) service requirements. This major milestone officially launched the Amsoil brand. The company has gone on to release many other industry-firsts, including: the first synthetic gear lube, first synthetic 2-cycle oil, and first 25,000-mile/1-year drain interval engine oil.

What Makes Amsoil Different?

Amsoil utilizes Group IV (PAO) and Group V base stocks, which are true synthetics not merely heavily refined petroleum as competitors use. The benefits of this range from better lubrication due to the molecules being more uniform in size to greater oxidation and thermal stability. Amsoil designs its proprietary additives in-house and its oils contain high-quality anti-wear (ZDDP), detergent, dispersant, anti-foam, and friction modifiers. Amsoil often publishes detailed results of ASTM test results in the name of transparency.

Heavy Duty Synthetic Engine Oil

With about 2,000 miles on our fresh Duramax engine build it was time to swap the break-in oil with a standard engine oil. For this we opted for Amsoil’s Signature Series 15W-40 Max-Duty diesel oil. Amsoil developed this engine oil specifically for high-horsepower diesel enthusiasts. The company claims that the oil delivers six-times more wear protection (based on the Detroit Diesel DD13 Scuffing Test using 5W-30 as a worst-case representation) and keeps cylinder liners looking like new longer. They also say this oil delivers up to 60-percent better turbo cleanliness (based on CAT C13 2^nd Ring Top Land Carbon testing) along with two-times better rust protection (based on the NMMA FC-W Rust Test).

Amsoil continues with the claims stating that its Signature Series diesel oil also resists oxidation and thickening effects of soot contamination, which is a big deal in diesel engines. It retains viscosity better after high-temperature service and provides up to 76-percent less oil consumption (based on the Caterpillar-1N oil consumption test).

Duramax engines require 10 quarts of oil and because we have installed a PPE oil pan our LB7 needed 11 quarts. We utilized three of Amsoil’s gallon jug options to fill our engine to the proper level.

Signature Series Fuel-Efficient Transmission Fluid

Similar to the Duramax engine, our Allison transmission was freshly built just 2,000 miles prior. At the time, we installed a PPE deep transmission pan, which provides four quarts of additional fluid capacity. While the fluid at this point was still fresh, we wanted to ensure that any material from the new clutches and steels wearing in has been removed. That said, we opted to change the spin-on Allison filter but not the internal filter.

For this we opted for Amsoil’s Signature Series Fuel Efficient automatic transmission fluid. Amsoil has designed this fluid for hard-working vehicles that live in severe service. Amsoil claims that this fluid handles heat so well that they are confident that a manufacturer’s severe-service drain interval can be doubled.

Amsoil Severe Gear Differential Service

Servicing the front and rear differentials is one of the easiest yet most commonly overlooked maintenance items on any pickup. When was the last time you even thought about the differentials under your truck? Go on, we’ll wait.

As part of our truck’s build, we swapped the factory gear sets for 4.56:1 units. We also ditched the rear GovLock differential for a mechanical limited-slip along with updating the axle shafts to chromoly steel units. Now that the new differentials were broken in, we wanted to ensure they were filled with fresh fluid.

For this we opted for Amsoil’s Severe Gear 75W-90 synthetic gear lube. Engineered for maximum performance in severe-duty applications, Amsoil’s gear lube delivers excellent performance in both hot and cold temperature extremes while maintaining viscosity for long-lasting protection against metal-to-metal contact. While good for any vehicle, these fluids are well-suited for towing, hauling, and racing applications.

Transfer Case Fluid Swap

One of the more difficult items to service on our Silverado 2500HD is the transfer case. The NP263 transfer case that GM used is a heavy-duty electronically shifted unit (manually shifted trucks got an NP261). Unfortunately, these transfer cases have an issue where the internal fluid pump may eventually wear a hole in the case allowing fluid to leak out. To remedy this, we installed a PPE Pump Rub kit.

These transfer cases, whether manually or electronically shifted, utilize GM Dexron automatic transmission fluid. Newer trucks with the company’s Auto Trak automatic transfer case take GM’s Auto Trak II fluid. The tech that did the pump rub kit install on our truck used the later. While not the end of the world, we wanted to get this incorrect fluid out and the right stuff in.

Premium Engine Antifreeze And Coolant

GM suggests performing a full coolant swap at 5 years or 150,000 miles and the recommendation for Ford and Ram diesel trucks is quite similar. Because our engine was a fresh build, we decided that it would be prudent to swap the cheap Dexcool fluid that we used with the fresh engine.

We recently went through the step-by-step process of swapping the fluid in a 2015 Duramax-powered Chevy Silverado, so we won’t rehash it here. The process is similar for all generations of Duramax. That said, our 2002 Silverado 2500HD has had the factory radiator swapped for a performance unit from Mishimoto, which includes a drain plug. This makes the process far easier.

For this service we opted for Amsoil’s line of passenger car and light truck antifreeze and coolant. This antifreeze uses a unique poly-organic acid (OAT) formulation that allows for its use in a wide variety of engines, including our Duramax diesel. It is phosphate, nitrate, nitrite, borate, and amine-free. And Amsoil says that it is compatible with all other types (colors) of antifreeze. In third-party testing (ASTM D2570), cast-iron and copper plates protected by Amsoil antifreeze showed virtually no signs of corrosion. Amsoil’s antifreeze is said to protect for up to 150,000 miles or 5 years of service.

Amsoil Injector Cleaner And Cetane Boost Fuel Additive

In additional to lubricants, Amsoil also offers a full line of diesel fuel additives that includes injector cleaners, cetane boosters, cold flow additives, and more. For this service opted to pick up a bottle of the company’s Injector Clean + Cetane Boost additive. Amsoil claims that this will boost cetane up to 8 points, can increase fuel economy up to 8 percent, reduce smoke and emission, and smooth out the idle.