I'm with Philscbx ... but I use a truck for many other towing reasons where a diesel 2500 is minimum requirements for me as I frequently get up into the 12-15k+ range for loads. Dodge 4x4 with Cummins for me. Owned 8 over the past 21 years, wouldn't have anything else for my towing needs. I haven't gotten the 6.7 dialed in yet for higher mpg, but all the 5.9s easily tuned in to 22-24 mpg highway empty and 15-16 towing (14.7 worst case but tipped scales slightly over 21k lbs) .
I upgraded my wife's '06 4runner to a '11 4runner due to the new interior redesign and it tows our '04 X2 well over short distances (the '06 struggled a bit). Haven't tried it for any long distances yet. Will likely look into a Tahoe or Suburban in a couple years when we upgrade again to get a bit more seating capacity/room, which is what we had prior to the '06 4runner when our kids were at home. The '11 4runner gets about 21-22 open highway, 17-18 around town/highway combination (wife's normal) and 12-13 towing boat/16 foot flatbed with Kubota RTV (but again, fairly short distances), has very large rotors with very good braking. We really like the Toyotas but they really aren't designed for someone over 6 foot tall IMO. I personnally would also look into the new Durango with Hemi as it offers 7400 (RWD)/ 7200 (AWD) towing and rating similar on MPG compared to the 4runner.