We Ran Rotella, Delo & Amsoil in 3 Diesels for 100,000 Miles — One DESTROYED the Others

Everybody wants to know which diesel oil wins: Shell Rotella, Chevron Delo, or Amsoil. So we followed three trucks toward 100,000 miles, and one engine came out visibly worse than the other two. But the reason it lost isn't the one every comparison video will sell you. After more than twenty years building and fixing diesels, I'll show you what actually decides whether your oil survives 100,000 miles, and why the brand on the bottle matters far less than the one number nobody reads. In this video we break down why all three oils meet the modern API CK-4 spec and are closer on the shelf than the internet admits, how 5W-40 and 15W-40 handle fuel dilution differently, how soot loading thickens good oil into engine-killing grit, and why total base number is the real countdown timer on your oil's life. No invented statistics, no fake studies, no brand worship. Just the mechanisms and the numbers that hold up. If this helps you protect your engine, subscribe for straight-talk diesel maintenance with no fabricated numbers. The used-oil analysis and drain-interval guide mentioned in the video is linked in the description. Disclaimer: This video is for general informational purposes only and is not a substitute for your manufacturer's service recommendations or professional diagnosis. Always follow your owner's manual and consult a qualified technician for your specific engine. Sources & Further Reading API CK-4 vs CJ-4 diesel oil classifications and performance changes: https://www.forconstructionpros.com/e... API Motor Oil Guide (CK-4 / FA-4 specifications): https://www.api.org/~/media/files/cer... Ford phosphorus concern and CK-4 wear-protection debate: https://www.lubesngreases.com/magazin... Amsoil diesel oil CK-4 status and Ford specification: https://www.amsoil.com/t/faq/ https://blog.amsoil.com/new-amsoil-sy... Diesel oil analysis — fuel dilution, soot, and wear metals: https://us.bddiesel.com/blogs/r-d-blo... https://www.dieselhub.com/maintenance... Total base number thresholds and condition-based oil changes: https://sterlinganalytical.com/oil-an... https://www.machinerylubrication.com/... Soot loading, additive depletion, and extended drain intervals: https://www.machinerylubrication.com/... https://semitruckoil.com/oil-analysis/ Lubrication failure and diesel component wear modes: https://goldfarbinc.com/blogs/news/ho... Real-world diesel oil pricing reference: https://fluidadvise.com/rotella-t6-vs...