Engines and modifications Sierra 2500HD IV (GMTK2XX) Crew Cab Long Box

6.6 Duramax TD V8 (445 Hp) Automatic

6.6 Duramax TD V8 (445 Hp) 4WD Automatic

6.6 Duramax TD V8 (397 Hp) Automatic

6.6 Duramax TD V8 (397 Hp) 4WD Automatic

6.0 V8 (360 Hp) Automatic

6.0 V8 (360 Hp) 4WD Automatic

6.0 V8 (301 Hp) Automatic CNG

6.0 V8 (301 Hp) 4WD Automatic CNG