Dumb newbie question

[Mike GMC]

This related to the V4-V8 modes.  When the engine switches to V4 mode, does it always run the same 4 cylinders or does it switch which 4 it uses to equalize run time?

[MiximusMaximus]

Ironically, I just thought this same question yesterday as I drove home. Just picked up a used 2015 SLT Crew so I am new to this rig as well.

[newdude]

Its a designated set of cylinders.  Cylinders 1 (driver side front most), 4 (passenger front middle), 6 (passenger rear middle) and 7 (driver rear most) are the active AFM cylinders, and 2, 3, 5 and 8 are the non active cylinders.  The system can allow an AFM V4 run time of up to 10 minutes to keep combustion temperatures happy when it fires back up. 

[Mike GMC]

Cool, thanks for clearing that up for me.

 

I just pulled the trigger last night on a 15 double cab Sierra SLT all terrain.  I was seeing the dash display switching back and forth on the highway on the way home and it made me think about it.

[MiximusMaximus]

Thanks gents. Now I know.