09/18/2026
Here is why preventative maintenance and using the proper fluids are vital to keep your diesel truck performing as it should!
2017 Ram with a 6.7L Cummins engine.
These are photos of the complete removal of the dashboard, and other interior components of a truck in order to replace the heater core.
The heater core photo is what can happen when the coolant system is not flushed often enough or the wrong fluid is used. The coolant can break down and create a thick sludge in the cooling / heating system clogging the heater core. This can cause the heating / cooling system to fail and leak onto the floorboard. This is a cross section of a heater core that was plugged and was flushed multiple times. Note the remaining sludge toward the bottom of the picture.
Remember, these aren’t grandpa’s diesel trucks, always use the proper fluids and check with us about preventative maintenance intervals.
Your diesel team at OFI