I was just curious so i looked things up. From this article, it looks like both a gas 2500 and diesel 3500 are in the mid 8's....pretty great for most cars/trucks. But it's not a sports car.
http://www.trucktrend.com/oftheyear/...sierra_hd.html
Fyi, the slowest Cayenne is listed at 7.5 to 60mph.