Last week, GM Authority exclusively brought you the very first images of GM’s upcoming 3.0L I-6 LM2 turbo-diesel Duramax engine. We were having a ball with the vector until GM issued a takedown notice, essentially blocking access to the file. But now, we managed to score more exclusive intel about the upcoming diesel mill, specifically about its cooling systems.
Specifically, GM Authority has learned that the 3.0L Duramax LM2 will utilize GM’s advanced cooling strategy known as Active Thermal Management. Initially implemented on GM’s turbo-charged 2.7L L3B and 2.0L LSY four-cylinder gasoline engines, Active Thermal Management uses a rotary valve system to distribute coolant through the engine in a targeted manner, sending heat where it’s needed to warm up the engine, thereby reducing friction and heating the cabin, or cooling when needed for high power operation.
An electric water pump is at the core of GM’s Active Thermal Management implementation. It further enhances the engine’s performance and efficiency by eliminating the parasitic drag that comes with a conventional engine-driven water pump. ATM also uses various cutting-edge features, including electronically-controlled ball valve modules to intelligently and precisely control the flow of coolant.
The result is that the engine warms up faster to achieve optimal operating temperature, resulting in better performance and higher efficiency.
To that end, the LM2 will use not one, but two electric coolant pumps – one engine coolant pump and an additional heater coolant pump – much like what we see on the L3B. This implementation is a first for a GM diesel engine.
It also seems that the LM2 will implement advanced coolant routing and the associated controls in much the same way as the L3B. In fact, the L3B goes beyond electric coolant pumps by utilizing cooling fans, a rotary valve system, and a coolant bypass valve. That combination would also be a first for a GM diesel motor.
To achieve active thermal management, the LM2 has numerous coolant temperature sensors placed at specific locations throughout the cooling system that were visible on the vector.
Besides pre-announcing the 3.0L Duramax when unveiling the 2019 Silverado and Sierra light duty trucks at the end of 2018/beginning of 2019, GM has remained very tight-lipped about the diesel engine. Leaks from late last year have pegged it at 282 horsepower and 450 pound-feet of torque in the 2019 Silverado 1500 and 2019 Sierra 1500.
Today’s information about the motor’s advanced cooling techniques via the Advanced Thermal Management system gives us a bit more intel about the engine that we did not have before.