Bad noise coming from rear brakes when...

Ok so I've been doing some home renovations ect.. point is I went to Home Depot today and picked up 6 pieces of 2x4, 5 sheets of drywall and 2 small bags of concrete mix. The bed of my truck sagged down maybe an inch...if that...

Everything was fine and dandy, didnt even think twice about it. Now the noise I got was really disturbing...

It sounds exactly like the noise you get when your brakes are about to go and you need new rotors and pads. That screeching scratching noise metal on metal.

This noise was going on non stop, from the rear of the truck with the bed loaded and I wasn't even tapping my brakes. Second I unloaded the truck, took it for a drive, noise is gone. So it only happens when my bed is loaded. WTF? Im so confused.. no idea what it is?

 

Ok... anybody got any idea?

 

Stock wheels and tires? If not, look for polished/worn/damaged parts near the wheel/tire/axle.

Next thing I'd think about is wheel bearings. Bad bearings + load could do that, I think.

 

The rear wheels don't have any bearings. It has a differential.

 

Wait what?

Yes you have rear bearings

But i would suspect aftermarket wheels, lift? carrier drop?