Here is my .02 on leaving it in fourwheel drive on dry pavment.
This is very hard on the front end, driveshafts, transfere case right back to the transmission. has anyone jacked up a fourwheel drive pickup that was still engaged in fourwheel drive? I will tell you the tires will rotate about 1/4 of a turn before you even get them all the way off the ground ( this is known as drivline wind-up) and is trying to release the force that is applied to your driveline. U-joints and CV-joints are the first to go when this is done much, then the transfere case is next.
Also if you ever had tires that were a different size on a fourwheel drive you may not be able to get it engaged and if you do, you probably won't be able to get it disengaged with out jacking it up to relieve this stress on the driveline ( happened to a friend whos truck was stuck in fourwheel drive and had me check it out, found he had a flat tire and put a smaller tire on it. Kind of funny he said it was making some weird noises..)
I know the truck will handle driving on dry pavement in fourwheel drive to some degree, just beware that you are not helping the driveline system. Hope this gives you some more insight on the do's and dont's. Been driving GM fourwheel drives since 1980 AND HAVE DONE ALL WORK ON MY VEHCILES. See Sig Good Day, Fran