Over the years, GM has changed a lot regarding the turbos they use on Duramax engines. Not only have they changed manufacturers a handful of times but each RPO has its own unique measurements for key components. This can make it a headache when trying to track down exactly what the measurements of your stock turbo are. Luckily we've compiled this list of stock Duramax turbo specifications along with other helpful information so you can get a good idea of what you're already working with before you dive into the sea of turbo upgrades these trucks have to choose from. However, while some turbos may have the same peak power output, the size and shape of specific components can affect things such as exhaust gas temperature, drive pressure, and turbo efficiency range.