Has anyone had problems with the brakes locking up on their Power stroke?

A couple of years ago I felt a vibration in the front end and when I stopped I could smell a burning plastic smell. When I pulled away from the light, the vibration quit and didn't happen gain for almost 6 months. The next time it happened I could see smoking coming from the driver's side front wheel. I took it straight to the shop, about a mile away. They didn't get around to looking at it for a day and then decided to change out the rear calipers for almost $900. I was skeptical that this was the issue, but they assured me that they had fixed the problem.

A couple of months later the same thing happened. This time they sent a mechanic out immediately and found that the left front brake rotor temp was over 800 degrees. They changed out the left front caliper and pads for another $400.

I still feel an occasional slight vibration and I'm wondering if they've actually fixed the root cause or just fixed the resulting symptoms. Has anyone else had a similar issue or any ideas on what's going on?

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2006 F-250 HD 6.0 Diesel

The brakes on these trucks can make an average mechanic look like a fool. When one of these trucks come in everything needs to be checked. And when a customer observes a problem at one wheel, just because it looks OK up on the lift really needs to be checked carefully.

They trucks on the '05+ vehicles still have the handicap of sliding pins corroding and causing a dragging or locked brake. Those are easy to find and repair as long as you look at the pins.

But with the '05+ trucks there have been an above normal instance of having the caliper lockup with a sticking piston. Those a mechanic is not going to visually see and often the only choice is to replace the caliper and hope that the rebuilt caliper is going to have a better result.

A third less common issue which happens more with age, with lifts, or mechanical damage during caliper removal is an internal tear in a brake hose which becomes a fluid trapping bubble of the inner ply.

Your first two descriptions are common for these situations:

• The pads are kept in contact with the rotor due to non- release situation.
  
• With the heat generated from contact friction the pads expand and generate more friction with the added pressure, increasing the temp and other adverse aspects.
  
• Increased hydraulic pressure or a rocking back of the pads can initiate a release of what is hanging the pads and
  you're able to continue on without a continuation of the problem.

If the vehicle has sat for a length of time just like any disc brake vehicles rust can form at the ends of the brake pads where they fit into the caliper brackets and also lock them in place. It doesn't sound like you are doing this though.

Is the occasional slight vibration during a stop or when not stopping?

If when not stopping it could be an indicator that the pads are contacting the rotor. If when stopping then it's likely that due to the brake hang up a hard spot has formed in the rotor(s) so the rotor will need to be replaced. Turning the rotor will not remove the hardness can vibration during stops will return in about 10 k miles.

Sorry guys I should have edited that statement after posting from my iPad. After just getting this iPad I find the self correcting of my typing mistakes takes a toll on what I'm writing. And now it's too late to edit.