You may or may not be aware that the current version of the 6.6-liter Duramax is heading down a dead end road. The last Duramax engine is scheduled to be produced for the 2016 model year. The 2017 GM trucks will feature the next version.
From what we have been able to piece together, the new engine will retain the Duramax name. It will, also, be an engine focused on meeting current and future emissions requirements as well as current and future power needs.
Sources close to the project are extremely excited for this new engine and have remarked that it will be a substantial step forward.
A few years ago, when we first learned about the project, it appears that GM was entertaining the “best of the best” type of parts. We heard rumors of steel pistons, aluminum blocks, compound turbochargers, and some other radical components.
Since that time, we have heard that the fuel system will be manufactured by Denso. We have not been able to nail down exactly what pump size or injectors yet.
We have not been able to confirm whether or not the new engine will feature an aluminum block or CGI (Compacted Graphite Iron). The aluminum block is unlikely if they opt for steel pistons. The aluminum block would indicate they are focused on weight savings for potential fuel economy gains, but steel pistons would indicate they are focused on durability and possibly performance.
From what we have learned from a recent oil presentation from Shell, is that new engines are going to be running hotter in hopes of yeilding better economy. The increased heat, would probably be why DMAX is interested in steel pistons. From what we have hear, this may be something all of the manufacturers are entertaining.
The video above is from The Fast Lane Truck. They have a lot of communication with OEM’s and are indicating that the new engine will be a 900 lb-ft of torque engine. Looking at the recent progression of horsepower and torque, it is unlikely this engine will be rated for what it is actually designed for. We have, also, not heard any unofficial numbers (not even from people within the program or close to it). Everyone we speak with basically says this will be a beast of an engine, but avoid answering anything specific (probably lots of NDA involved in developing a new engine).
We will keep our ear to the ground and continue to bring you the latest.