I was on my way home today and my truck (04 Lariat SCREW 4x4)started making a really loud squealing noise. I pulled over and it stopped. About two miles later it started doing it again, but this time it made a loud thud a few seconds after it stopped. Anyone have a problem like this or have any clue what it might be?

 

You didnt hit a door-to-door swine salesman, did you? Is the thud only audible, or can you feel it in the truck? Did it make a noise while moving, or at a stop?

 

It made the noise while moving (approx 55). I felt the thud. I thought that maybe the brakes were sticking and then they released, but I am not sure.

 

No offense, but are you 100% sure the E-brake wasn't engaged a little?
Chris

 

None taken. I've never used the e-brake. The noise was coming from the front. Isn't the e-brake generally attached to the rear brakes?

 

could be the front caliper sticking

 

It also could be a vacuum hub going out on the front. I had this happen on a new Expedition I was test driving. It started whining, and then thumping. After I rolled the window down I could tell it was a gringing noise, and the drivers side hub was jumping in and out of gear.

Since the Expedition had an auto 4x4 setting, I put the selector there and engaged both hubs. The noise stopped, and the dealer had to replace the front hub with only 17 miles on it.

 

It was the 4x4 trying to engage. He said the part that controlled it(can't remember what he called it) was so hot he couldn't touch it. The dealer ordered the part today. Hopefully, it didn't damage anything else.