Suspected Suspension Problem?

[mecijan]

I recently bought a 2009 GMC Sierra as a 3rd owner with ~200k miles. I normally drive a hummer h2 with an air suspension and feels bouncy. In this case, the truck doesn’t... in fact I can feel everything on the road, every pot hole to every indent on the road. I check the struts and shocks and they are Bilstein 5100. I’m wondering if there’s a problem with the suspension acting as stated above. Also when I drive steady (20-40mph) without accelerating nor brake, the whole car rumbles as if I was driving on gravel. What’s causing that problem?