Which shocks did you install? (Part numbers that is).

They are probably just stiffer and you are not used to it. I put in 20% stiffer front and back bils and I definitely notice but they are so much better than stock.

I think that people have the misconception that when you replace shocks you should expect to feel like you are "riding on air." That's just not the case, especially in a heavy truck.

Take it offroad and you'll appreciate the stiffer ride.