My 97 regular cab gives a pretty good secondary bounce when I go over even minor bumps in the road. It's not a tire bounce. It feels like if you had a heavy box in the bed and it bounced up and slammed down when you go over a bump. I checked the spare and it is tight and secure. Nothing underneath seems loose. No attachments holding the bed to the frame seem loose or missing. The leaf springs are slightly out of line but tight.
Is there something fairly inexpensive that might be done to the suspension? New or added leaf? I replaced the shocks when I first started feeling the bounce.