2007isx engine brake problem

[manny87]

Harness is fine.
I dnt think there is fuel in the oil. I will check the bubbles for airation but if thats the case my oil pressure guage should fluctuate .
Cummins guy checked the brakes with brake out harness. And they think its fine. After they replace the rockers and shafts, brakes do get louder. But they dont hold the speed of truck on hill even with empty trailer.