2005 F-150 4x4 Screw, 5.4, 51k miles

On the way to work this morning I noticed what I thought was something burning, almost smelled electrical. When I came to a stop light in order to pull off the road I saw smoke coming from underneath and thought I was going to have to call the F.D. I looked under the hood and underneath the truck and didn't see anything leaking or thank God, no fire. After looking around it appeared the smell was coming from the left front calipar or rotor and could feel major heat radiating and checked the right front and that appeared normal. The brakes have already been replaced by the dealer once when I had bad shuttering when I applied the brakes. I am awaiting a call from the dealer now and don't know whether to drive it in or have it towed. Brakes, at the moment, work fine. Anyone had anything similar or know what might be happening. I searched the forum and didn't see anything listed. Also, sorry for the long post.
Thanks in advance for any help.

 

I personally would drive it to a service dept. Drive slowly and be aware of brake usage.

It sounds like the caliper stuck on the hot side.

good luck!