Popping noise going over 42- 43 MPH
 

2000 Chevy Blazer 4X4 - 4 door
I was at a store the other day and backed out of a slot. Heard pop/thud type noise thought it was a soda can I backed over, (I seen it smashed after whole before), Anyway, now when I go over 42 - 43 MPH hour I hear this popping / thud noise from the front around the engine compartment. I don't feel anything in the floor board or from the steering wheel. I only does it when I exceed 42 - 43 MPH hour. Does not do it while breaking, turning or being under that speed. I thought at first I blew a coil pack or sparkplug, but there is no check engine light. Can someone help please?
Thank You

Sometimes the bolts that hold the hood on loosen up and the clunking sounds like it is coming from somewhere else. Search here for the repair, which is a pair of conical washers available at the dealer for about $5 a pair.

Thank you, its not the hood