Do I need an weight distributing hitch for my Colorado?

I hope the spring packs in the current Colorados are better than the previous generation. A friend of mine had a GMC Canyon and that thing would sag almost to the axle with a mere 150lbs of tongue weight!

For the record, with NOTHING in the bed, and nobody in the cab.

He had to take it to a spring shop to have the springs recurved and a leaf added. Even then it wasn't that great. The same 150lbs would still drop the rear end 2".