Yep, another keep the one you have and pay it off vote. Doesn't make financial sense to put that money in a CD earning less interest then what you are no doubt paying on your loan. It may sound good, but it really doesn't make any sense to do that. On the other hand, if your truck is paid off, you can save the payment you'd normally make into some sort of safety net account while at the same time knowing that your truck is yours.
If you decide to get something else, though, I like the Denali looks better. The Escalade is just too...I dunno....rectangled out everywhere possible....lol.