The truck clearly is the center of interest here, but it's kind of dark and muddy looking. I don't care much for HDR, but can see why you went that way. I would crop tighter on the car and concentrate on bringing out some more shadow detail (without losing the blacks) in the raw conversion. The surrounding scenery doesn't really add anything, so I'd center the car and leave only a very small amount around it. The car itself is asymmetric so I don't think a centered composition would be undesirable in this case.