The Great Oil Showdown: A Diesel Shop’s Journey from Disaster to Discovery
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By Vinny Himes
Twenty years ago, in a bustling diesel shop in Post Falls, Idaho, I worked as an engine builder. It was an era marked by a fierce rivalry between two oil salesmen: one from Ed’soil (name changed for legal purposes) and the other from Schaeffer’s. Both were determined to convince the shop owner to give their products a shot. Little did we know, this rivalry would lead us through a nightmare and into a revelation.
Our journey began with Ed’soil. Enthralled by the salesman’s confident promises, we decided to try their oil. He claimed it could extend oil change intervals to 20,000, even 30,000 miles. Trusting his word, we repeated these claims to our customers. But soon, the repercussions hit us hard. Turbos, injectors, and hydraulic lifters began to fail. The trusted engines we maintained started to suffer, and so did our reputation. Our customers faced hefty repair bills due to our misguided advice. To add insult to injury, Ed’soil’s oil left a stubborn, black stain on chrome-plated wrenches and sockets, a mark that took weeks to wash off our hands.
Amid this chaos, the Schaeffer’s salesman continued to visit, persistently promising a better alternative. After our harrowing experience, we were in no mood for more sales pitches. However, his persistence and a demonstration caught our attention.
The Schaeffer’s salesman proposed a test: using a 3-horsepower electric motor, he would demonstrate the oil’s performance with an oil bath bearing. With other oils, a slight pressure on the handle caused the bearing to smoke and seize. But with Schaeffer’s oil, even with both of us hanging off the handle, the bearing ran smoothly without smoke.
Skeptical, I challenged him with my test. “I’m building a 12-valve Cummins engine right now,” I said. “When I finish, I’ll call you, and we’ll see how your oil performs.”
True to my word, I completed the engine and called him. He arrived with three gallons of Schaeffer’s diesel engine oil. We filled the freshly built engine and placed it on our engine stand. Following a 20-minute camshaft break-in at 2,000 RPM, I refilled the test stand’s fuel tank, revved the engine back to 2,000 RPM, and removed the oil drain plug. As the oil drained, the engine continued to run at 2,000 RPM until it ran out of fuel. Throughout this test, I monitored the engine with a radar temperature gun. Remarkably, it never overheated, slowed down, or changed RPM.
This extraordinary performance convinced me beyond a doubt. Schaeffer’s oil had proven its worth in the most rigorous test I could devise. From that day forward, I’ve used Schaeffer’s oil in all my vehicles and will continue to do so for as long as it’s available.
This experience taught me a vital lesson about trust and performance. It’s a story of how we learned the hard way, but ultimately discovered a product we could truly rely on.
Vinny's Pick
S&B Cold Air Intake Cotton Cleanable (75-5075-1) for 2011-2016 Duramax LML
The S&B Cold Air Intake Cotton Cleanable 75-5075-1 fits 2011-2016 Duramax LML engines. It uses a reusable cotton cleanable air filter designed for improved airflow and long-term service life. The system includes a durable silicone intake tube and heat shield for cooler intake air. Improved airflow helps support throttle response, horsepower, and engine efficiency. The 75-5075-1 installs using basic hand tools and included hardware.
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One thought on “The Great Oil Showdown: A Diesel Shop’s Journey from Disaster to Discovery”
You recommend Schaeffer’s over T-6 in a 6.0 ? Last time I tried a different oil I ended up replacing 8 injectors. Maybe a coincidence but I’m a little snake bit lol….