Yes the car has AIR Shocks too.
Will check crossmember! It's a big bag when you hit a good bump. The rest is buzz rattle creak and clank
I checked the rear shock mount for damage and cracks. It's 100% intact!
I put a wrench on the u bolts holding the rear end and lower shock mount to the spring. Wasn't tight wasn't loose either !
I put the impact gun on em and got two full turns on each nut!
I still have it on jack stands. Going to nut and bolt it from front to back tonight!
Update;
Friday night I checked every nut and bolt under the car.
As mentioned before. Spring u bolts were loose. Motor mounts were loose, one bellhousing bolt was loose.
I tightened everything!
Much better!
Since the shock is bolted to the u-bolt plate maybe that was your noise??