Currently have a '03 GMC Sierra 5.3 4X4. Tows my tin (Lowe V-hull) very well but only gets 13 mpg around town right now and 9-10 mpg towing (11 on a great day). The GMC is getting a little old and has over 200K on it. Things are starting to pop up that could be signs of $$$$ repair bills coming.
The Colorado diesel version I'm looking at (long bed, Z71) boasts 30 mpg highway, 23 around town. Have seen 17-24 mpg towing posted on other forums. 369 lbs/ft torque at 2000 rpm vs my 325 at 4500 rpm (where i'm hardly ever at). But inside and bed room are a lot smaller although I'll be moving from an extended cab to a crew version.
Picking one up tomorrow night for an extended test drive. Hope to be impressed enough by it to warrant a new truck payment.
And we're supposed to get an inch of snow Saturday so I may get to see how it does in it.