The chassis cab use a standard Variable Geometry Turbocharger (VGT) operated with engine oil pressure that is controlled by the PCM. This turbocharger does not incorporate a wastegate.
The turbocharger pickup models use a DualBoost turbocharger.
This turbocharger has one exhaust turbine, two intake compressors and incorporates a wastegate. The exhaust turbine has variable vanes that change with engine oil pressure from a PCM-controlled solenoid.
The air intake system includes a MAF and IAT sensors integrated into one unit. The MAF/IAT sensor is located in
the air inlet tube after the air filter.
The air filter is located on the passenger side of the engine compartment in front of the battery.
The air filter housing includes a non-electrical filter minder to measure inlet restriction. When the filter element
becomes contaminated beyond useful limits, the filter minder visually indicates the need for replacement.
Air is drawn through the air filter then past the Mass Air Flow (MAF) and Intake Air Temperature (IAT) sensors. The
MAF sensor measures the mass of the air entering the engine and IAT obtains the temperature. Next, the air enters
the compressor side of the turbocharger through the lower intake manifold. The air is compressed above atmospheric pressure. The compressing process causes the air to heat up. Directing the air to an air to coolant Charge Air Cooler (CAC). From the CAC the air passes the CAC temperature sensor and through the intake throttle body and into the other side of the lower intake manifold. Inside the lower intake manifold the air mixes with EGR gases (if EGR valve is open), travels to the upper intake manifold, and through the right and left side rocker covers to the intake ports of the cylinder heads.
Exhaust gases exit the exhaust ports into the inboard exhaust manifolds. Exhaust gases are directed to the dual inlet
of the turbo via the right and left side up-pipe. The exhaust spins the turbine wheel inside the turbocharger. The turbine wheel spins the compressor wheel(s) via their common shaft. Some of the exhaust from the passenger side manifold is directed to the EGR valve through the EGR inlet pipe. When the EGR valve is being operated, exhaust flow goes through the valve then either through the EGR cooler or bypassing the cooler. This is done by the EGR cooler bypass valve. The exhaust gas enters the lower intake manifold and combines with the fresh air.
The oil filter is a spin-on style mounted on the right side of the oil pan.
The oil cooler is mounted on the oil pan of the engine and uses engine coolant to dissipate heat from the engine oil.
The coolant and oil are separated by multiple plates that create passages in the oil cooler.
After oil has been cooled, it exits the oil cooler and travels through the oil pan to the oil filter.
There is an oil manifold in each cylinder head that sprays oil onto the rocker arms and valve springs for cooling and lubrication.
The 6.7L engine incorporates piston cooling jets that spray oil into a hole in the bottom of the piston to cool the top
of the piston.
The oil jets bolt into the bottom of the block and direct the oil into the piston.
The oil pressure regulator valve is located in the oil pump cover on the back of the front cover.