It's amazing what vapors will get pulled into the cowls on newer vehicles these days. We had a similar issue with a 2016 Freightliner Cascadia but it was blow by from the engine. It took us 15 months to get Cummins to warranty it. The truck was using 3 gallons of oil in between oil changes. The problem was no one was writing it up or documenting the oil consumption. We had to document the oil usage for a year before they would even talk to us. Luckily our company has a warranty department and they fought cummins. Cummins was just trying to time us out on our warranty. Un freaking believable....

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