are you actually using more than one exposure? The posting above is telling me that you are using one exposure.
If you are using one exposure you are not doing HDR but rather tonemapping.
Either way I would say out of your two photos to choose from the first would be better only because the sky is not blown out but in both the sky is dirty.
The first one shows a little more detail in the dark areas than the second one - note the the tire and the foliage to the right of the truck (viewer's left).