Fourth 2.8L Duramax Used Oil Analysis

Here we have my 4th used oil analysis from my 2018 Colorado with the 2.8L Duramax engine. I now have over 36,000 miles on the truck (I skipped the analysis on a couple oil changes in between this and the last one) and I’ve had zero issues with the powertrain, nor the emissions systems.

I treat every tank of fuel with either All-in-One or Diesel Injector Clean + Cetane Boost depending on the season. The truck starts every time, idles perfectly, and has as much power as one would expect from the 181 horsepower/369 lbs/ft rating.

The truck is no longer my daily driver. In fact, my wife drives it more than I do and so fuel mileage has tapered off a bit as she does more driving around town than I used to. Previously 2/3 of my mileage was highway.

With a TBN of 4.3, I agree with Blackstone’s analysis that the oil has more life, especially considering this is the second UOA now with a TBN above 4 with over 8000 miles on the oil. It also pleases me that the insoluble (soot) levels are low. Despite still being within the powertrain warranty, I think I will take their advice and do a 10k interval and see how the numbers look.

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Originally published on MidMichigan Oil LLC, independent AMSOIL dealer, restored from archive.