now i know that first you have to shoot out this areas bosses treads but what do i do after that?

k so you mean after it smashes into them

If you didn't already get past it: When it smashes into the platforms grab a screw with the claw and pull it out by repeatedly pressing the claw button. When you get all three, just shoot the dude that is now exposed.

My brother just chucked a grenade at it and it exploded.... :p

^^^^
That's What I Did!!

"If you didn't already get past it: When it smashes into the platforms grab a screw with the claw and pull it out by repeatedly pressing the claw button. When you get all three, just shoot the dude that is now exposed."

The thing noone has mentioned that can be confusing is that in order to actually "lure" him at the platform you have to run right up to the machine so that you are too close for the bombs.

He will then rev up his engine, do a burnout, charge to the left, smash into the platforms and stall out.