They call it displacement on demand. How do you know its switching? Is there a guage or light of some sort? I love the new impala's, I have to get an ss sooner or later. Gotta have that small block v8. Is it a 5.3 or 5.0? I wish it were a 5.7. I love the chevy 350's. Also too bad its not rear wheel drive.... or is it?