Clunk in rear box area

i have a 2011 Tacoma , recently I’ve been hearing a loud clunk when I hit a good bump; nothing is in the box, my mech. Figured it could be the box separating( plastic clips), I’m not sure but it sounds worse than that. Also last year I put heavy duty leafs on (4) & a 2.5” lift on the front. Any guesses would be greatly appreciated, thx.

 

I had the same thing happening to me about a year ago after my rear bumper was installed...turns out the bracket that holds the rear bumper in place (to the frame) had a couple of loose bolts, causing the whole thing to move up and down when going over bumps. Made a pretty loud "CLANK" sound until I tightened them.

 

Welcome to TW.... Is there anything lose in storage compartments behind or under back seats?

 

great, thx I’ll check the bumper.

 

No nothing loose behind the seats, definately something outside the cab, thx

 

Welcome to TW! Squeaky leafs maybe?