Here is some more info on IED effects on HMMWVS. The explosive force of an IED tends to rip things apart and leave jagged edges, not smooth dents. Usually, the vehicle has either minor damage if it is not a direct hit or not close enough, as in this pic.

(Notice how the hood is cracked and broken, but not crumpled.)
Or it catches fire and totally melts down, like these:



Sometimes they don't catch fire and melt, but the damage is usually quite extensive:


Hope that helps.