2017 Cummins Ram 6.7L; Schaeffer 5w-40 8.1k mi

Jul 6, 2020
2017 Ram 3500 6spd manual. 6.7 Cummins First time UOA. the truck is deleted and the EGR coolar has been removed for about 40k miles. im just a bit worried about the potassium levels. two oil changes ago i ran Schaeffers 5w40, not sure if they happen to have a lot of potassium and its left over. truck is not using coolant from what i can see. oil is Rotella T6 5w40 [IMG]https://www.flickr.com/gp/[email protected]/4Kn5H4[/IMG]

Last edited by a moderator:
Looks like leftovers from the EGR system taking awhile to washout. Mine took a few changes to washout as well, just watch for it to trend down on the next few UOA's.
Mine had high potassium first UOA, which is dropping. I think one suggestion which someone suggested it was leaching from the intercooler. Keep an eye on the coolant level and if it never drops, you are in the clear.
I had a similar report in February on my 2500 Cummins. My indicator of flux was believed to be the higher aluminum and potassium. The one thing that would lead me to wonder about a bigger issue is the the lack of a number for antifreeze. I did a 3,000 mile sample to check and I posted the results for reference. You can see the scan at this link... https://www.bobistheoilguy.com/foru...500-delvac-15w40-3-000-miles#Post5471091 As others have stated if you aren't loosing coolant don't sweat the details too much.