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.  

2001-2004 Duramax LB7 - IHI RHG6

2004.5-2005 Duramax LLY - Garrett GT3788VA

Compressor Wheel Blade Count: 11
Compressor Wheel Inducer: 62.8mm
Compressor Wheel Exducer: 88mm
Turbine Wheel Blade Count: 13
Stock Turbine Wheel Inducer: 71.3mm
Stock Turbine Wheel Exducer: 65.7mm
Stock Vane Height (Exhaust Volute Gap): 14.4mm
Stock Boost Rating: 30psi
Max Boost Rating: 37psi
Max HP Rating: 530hp

2006-2007 Duramax LBZ - Garrett GT3788VA

2007.5-2010 Duramax LMM - Garrett GT3788VA

Compressor Wheel Blade Count: 11
Compressor Wheel Inducer: 60.5mm
Compressor Wheel Exducer: 87.9mm
Turbine Wheel Blade Count: 13
Stock Turbine Wheel Inducer: 66mm
Stock Turbine Wheel Exducer: 63.4mm
Stock Vane Height (Exhaust Volute Gap): 11.55mm
Stock Boost Rating: 30psi
Max Boost Rating: 37psi
Max HP Rating: 530hp 

2011-2016 Duramax LML - Garrett GT3788VA

Compressor Wheel Blade Count: 11
Compressor Wheel Inducer: 60.5mm
Compressor Wheel Exducer: 87.9mm
Turbine Wheel Blade Count: 13
Stock Turbine Wheel Inducer: 66mm
Stock Turbine Wheel Exducer: 62.0mm
Stock Vane Height (Exhaust Volute Gap): 10.53mm
Stock Boost Rating: 30psi
Max Boost Rating: 39psi
Max HP Rating: 530hp 

2017-2022 Duramax L5P -  BorgWarner B2BV-70A