6.4L - Failed EGR Cooler

It’s a fact that a diesel engine functions very differently from a standard gas-powered vehicle. Diesel engines require specific tools, and technicians require specific training in order to correctly service these engines to provide years of reliable performance. View the main services we offer, give us a call, or request an estimate online to get started!

Failed EGR coolers run across the board with many diesel engines.

Most notably on the 6.0 Powerstroke engine. An EGR cooler works by taking used exhaust gases from one side of the engine, running them through a chamber that has sealed coolant passages, and allowing the hot air to cool down using the vehicle's water-based cooling system. Once the exhaust air has been cooled, it’s then routed back into the intake for engine consumption. Most often, the passages which the coolant runs through, begin to deteriorate allowing coolant to leak into the exhaust system after the vehicle has been turned off. This can sometimes cause a white, sweet-smelling, smoke to exit the tailpipe. If the leak is bad enough, this smoke then presents itself after the vehicle has warmed up as the leak is so bad that it continues to leak when the vehicle is in motion. A bad EGR cooler can also fill your engine's cooling system with exhaust pressure giving the impression of a blown head gasket. The reason the coolant reservoir will sometimes bubble over is due to the increased pressure. The cooling system is usually designed to handle between 16-20PSI. With a bad EGR cooler, these pressures can sometimes reach 25PSI, well over the designed capacity. Usually, bad EGR coolers don’t cause major cylinder issues on the 6.4, unlike the 6.0, because their air inlet port (hot side of EGR) sits at the top of the engine. We do see faulty EGR coolers cause blown head gaskets. The faulty EGR cooler isn’t to “blame” for blown head gaskets, it’s actually the loss of coolant through the

faulty EGR cooler which causes the blown head gasket.