I did a front brake job on my 2003 Navigator. While doing the brake job the Right front pads were worn down to the metal shoe. The Left front shoe still had pad left. After the brake job, there is a load sqeaking noise on the right front side and appears to be sticking. Any ideas?

 

By "brake job" do you mean you replaced the pads, the rotors, and the calipers?

How is the hub assembly? Does it show any signs of looseness?

Did your "brake job" include cleaning up the sliderpins and re-lubing them?

When the brake sticks, does opening the bleeder valve free up the brake?

 

I replaced the pads - everything else looked fine.

 

You will most likely have to either remove the piston and clean the cylinder thoroughly or replace the caliper. It sounds like the piston is stuck due to rust or debris accumulating in the cylinder. Remove the piston and inspect the cylinder, if it is pitted, replace it.

 

2003Navi,
Did you open the bleeder valve when compressing the cylinder piston when re-assembling? Some do not and force the old contaminated brake fluid back into the cylinder.
If you didn't flush, I'd recommend flushing the whole system as changing brake fluid regularly is a factory standard practice.
Also, to Jim's point, did you use brake grease to lube the sliders? How did the inside pad wear compare to the outside pad? If sticking, you will see one side wear much faster than the other.
Lastly, not sure if 2wd or 4wd but did you grease the wheel bearings (both in and out) if 2wd?
This should also be done regularly when putting on new pads. Only takes another 15-20 minutes max.
The last thing is that you said the pad went down to metal. If so, have you mic'd the disc to ensure the wear hasn't exceeded mfg specs? If the wear groove on the edge of the disc is excessive, new pads will get caught up on this ledge until "worn in."

 

What would make you think the fluid became contaminated inside of a closed system? Opening the bleeder screw is what can contaminate fluid that was not previously.

 

Overall this sounds like you didn't put any antifriction on your pads (the squeak you speak of). Second, if one pad was worn more than another, I highly suspect a sticking caliper. In that case you can either rebuild them yourself (about $10 ea.) if you have a honer and some emery cloth and time or you can simply replace the calipers (about $50 ea.). I initially suggest replacement simply because if you have pitting, you will need to replace those pitted parts and now your pushing toward that $50 and your time chasing parts.
I would replace the rotors (moderately priced) and do the bearings (there cheap) while your at it.
Be sure when replacing calipers you use a clear jar with a clear hose that fits snug onto your bleeder. In that jar you will fill it about 1/4 the way with brake fluid and put the hose into that fluid, making sure its submerged. Slowly continually pump the pedal to the floor to evacuate the air. As you pump the air out, fluid will replace it...but the fluid must be visible through the whole hose (thus a clear one) so you know when all the air has been purged. You close off your bleeder while the hose is still attached and move to the next caliper to restart the process.
Buy a large container of brake fluid, you will be 'flushing' old contaminates and you don't want to put them back into your system if you were thinking you could just recycle it. Also don't let the resevoir get below half full before refilling it as you do this process (you may have to fill it 3 or 4 times or more).

 

"Contamination" maybe isn't the right word, however, the most amount of heat occurs closest to the calipers/pads. Heat as we all know, is the biggest factor in breaking down most all oils/fluids including brake fluid. As mfg's suggest, changing brake fluid is a requirement of most. How many times have you seen blackish brake fluid in a "closed" system?
Pumping the brake fluid back into the system rather than removing it, could very well help in creating additional braking issues. I don't think this is any secret but necessary for those changing brakes to understand.
Alloro,
You of all people, know when trying to help others with limited information, is still a guessing game, trying to give the best possible info to help.
Also, bleeding your brakes properly should not result in any possible contamination.
Maybe you have the remedy to share?