Originally Posted by rangerignorance
I shut off the motor and jacked up the back passenger wheel. The wheel spun like 1-2 rotations.
Uh, yeah, don't do that!
What year truck do you have? If it's an '01 or newer (or whenever the heck the change was, '02+ for sure) then you don't even have dis/engagable hubs anyhow. Ford elmintated the hub disconnect and went to a 'live axle' setup where the front half shafts are ALWAYS connected to the wheels, regardless of transfer case position. The upside is there are no pneumatic or electronic hubs to break anymore. The downside is your CVs are ALWAYS turning (and racking up wear and tear). My service advisor read me a line that it keeps the boots plyable and prevents them from dryrotting. I'm not sold.
This means you should never ever run 4WD on dry pavement, and even then you should never ever ever ever turn the steering wheel. As has been said, your fortunate that it just bound and didn't break. Were you do have thinner tires and/or heavier duty drive train components I think you would get wheel hop instead, as the tire contact patch w/ the ground would be the weak point. My friends that have been driving 4WD trucks for years say they've had that happen in the past. I haven't had the gonads to try it..