I have not towed boats and the like as some of the other users have, but I have had so much crush n' run gravel in the bed on a twenty mile errand the rear tires looked flat. I couldn't believe the truck could carry that much weight. I didn't name it "Ol' Reliable" for nothing.

Like it has been mentioned, your main concern should be braking distance. And you did not mention the terrain either. But a "flatland" tow should be fine if you use care- for example double you normal following distance. You will tax the brakes more than the chassis, guaranteed.

Use common sense and be mindful of hills and brakes and you should be fine.