There is a story here.... I have a 2007 Dodge 3500 HD cab & chassis with a flatbed.....Very low mileage currently at 128600, I either drive 16 miles a day to work, or it is pulling a load.... at some point in 2013, I assumed that an oil change was flubbed and not refilled, because i found it to be below the safe level and then it would continue to use oil at a pretty good clip (about a gallon every 3000 miles) so assuming that the damage had been done, I just was vigilant about checking the oil and adding as needed, my go to mechanic, found no leaks or apparent reason for oil consumption...(has been deleted, and though I got message saying catalyst was full, i disregarded since it was gone).. In late 2015, on an extended trip to go get a job trailer in El Paso , 900 miles(at 121,000 miles). It fell out and started knocking seriously. So we parked it and had it carried home. VERY Good well trusted mechanic (head mechanic for LARGE road construction firm) installed rebuilt engine, from a reputable, professional rebuilding company. New water pump, belts, hoses, stat, iat sensor, fuel rail sensor, had all injectors tested and replaced 2, found ccv filter very saturated and heavy, wondered it that had any bearing on any of this... Has run VERY well and every thing was awesome from 121,000 to about 126,000. Had been checking oil regularly and at 126,000 I checked oil to find it was below the line. 1 quart brought it back to safe line. after that it has been needing about a quart about every 500 miles. There are no visible leaks, and nothing on carport. today at 128,600, took to shop to have ccv filter replaced to see how heavy it is..... The only clue it gives to ANYTHING being wrong is a slight oil smell after driving. like a bit was spilt on valve cover. Am I being paranoid..... I was easy during break in, and even after that, I usually don't drive it far enough to really give it a work out. Will take it on a road trip to Austin next weekend to try to blow out the cobwebs. But don't really know whats up this consumption. I really love this truck and plan on driving it a long time, unless I just KEEP having engine trouble... Any body ran across any of this before ?

 

Turbo leaking oil?

 

If it is the turbo leaking it can cause a runaway condition...need to check that out sooner than later.

 

The turbo would be my first suggestion also.
virtually no good test.