This is a common problem. You turn the key, it feels suspiciously easy to twist, and the truck won't start. You may or may not even get power to the accessories.

The problem is a broken ignition actuator rod. It connects the ignition key assembly to the ignition switch, down on the lower end of the steering wheel shaft housing. The repair is a bit tedious, and requires patience. But good news, the actuator, a cheesy little piece of pot metal, only costs about $13 today in 2018.

I faced it down today in freezing weather. Not being born yesterday, I got a little electric heater from the house, ran an extension cord to the truck, and let that little sucker work for 30 minutes before I started.

There are dozens of videos on this fix. Many are useless, dude holding the phone in one hand and pliers in another hand. This one is a bit like that but at least you can see a lot of what he did. BUTT, he cut off the end of the actuator rod. DON'T DO THAT. It means that you could switch the ignition off all the way to locking the steering wheel, accidentally, while driving.

But you can use this video with others. You have to watch at least two because they are mostly bad. Here's another
When you've watched enough to blur your eyes, watch this one, it's the best of the lot but he still missed the big circlips on the steering shaft.
The trick I used was to get a helper to push down on the adjustable steering bit all the way down. That lets you get the new actuator in place, assuming you have removed the two side pins first, and the circlips on the steering shaft itself.

While in there, I removed years of congealed grease from the lock cylinder and its little rack and pinion. Toothbrush and acetone! A full greasing with silicone grease and it's as smooth as sex now. I hope we are allowed to say that.