Back of suv makes creaking noise over bumps. sounds like an old matress
Could be the shocks or struts maybe.
Squeaking sounds at the back of your SUV that sound like the springs of a rusty mattress are as a result of dry hub bushings. To fix the problem, remove the wheel and apply grease on the bushings.
What kind of suv, this would help tell us whether it is springs or shocks. Sounds like they need to be replaced. The rubber in the mounting brackets could be moving while the car bounces.
would be nice to know what kind of suv, possable dry sway bar bushings