I do not want to hijack the thread, but. I saw an issue with a drivability concern. My 04 ZHP had a surge or bucking while gently accelerating. I took it to the dealer with the latest software update that I found listed on the forum. When I got the car back it had cured that problem with an added benifit - i had fantastic throttle response. A light press of the pedal & she ran smooth & had instant response. Well worth doing - my opinion.