For me it looks like from left to right, Overkill, Hardhead, Blaster, and this may be wishful thinking on my part, but the left most bot kind of has a FortMax silhouette, with the helicopter landing pad on the side of his leg. And FortMax did have a bit of a pee-pee in G1. They just maxxed it out this time
But then again its forearms look lie they have claws for kibble, so I'm probably off base with the FortMax guess.