I began hearing this sound as well about three weeks ago. I have one question and it is probably a stupid one, what is flock?

 

Check your trailer hitch, if you have the one that mounted up underneath the bumper. Had that exact same squeak and issue and low and behold it was the hitch...that was AFTER I took a ride in the cargo area to try to pin it down. Bolt was loose from installation, snugged everything up and viola...no more squeaks.

BC

 

Try wrapping the "D" latch for the rear seats w/ some cloth tape. I had the same issue and that solved it.

 

I have the same issue with my 2015 2500 Dodge Ram. Had someone sit in the rear seat as I drove around, we thought it was the side step as they were a little loose, tightened up but squeak still there. With radio turned down its very annoying. Please help

 

R_camacho26,

As your truck is a 2015 model, are you still under warranty? If so, I would recommend a trip to your local dealership.

Has this happened since you first bought the truck?