09-10-2016,
(09-09-2016 )garrett5150 Wrote: [ -> ]it didn't change when oil thermostat was removed. emissions ok per cummins. year is 2009 with 750,000 miles. it just started doing this all at once been great until about a month ago
I'm wondering if it is not your oil cooler itself failing. I had mine replaced when we did the in frame after discussing this with Unilevers. Those coolers do fail according to him, and are often missed when doing an in frame as they are not really on the radar, and do have a shelf life.