Driver-selectable Fuel-saver Mode

[miketfr]

The 2010 Yukon brochure contains the following statement "And for 2010, driver-selectable Fuel-Saver mode allows you to stay in 4-cylinder mode longer". I couldn't find anything in the Owner's Manual and the dealer never heard of it. Does anyone have any info?

[brims]

If that's true, anyone that puts it into V4 mode will hate it. No power in V4 mode, that's why it only activates when coasting downhill or really flat surfaces.

 

Maybe it allows you to manually disable AFM when you don't want it to go into V4 mode.