Dean dying in season 3 finale

when dean died in the season 3 finale, wasn't there a way to break the deal & try to fight it?? the thing that killed dean was an invisible dog or werewolf (whatever it was) couldn't they just use the cult to shoot it even though you can't see it?! i wish that dean & sam should have done the same thing they did in season 2 with the crossroad blues when they were trying to help the guy who made a deal with the demon & dean made the demon to break the deal. so why couldn't they do the same

I hope this will answer your questions:

Unfortunately, the character "Bela" stole and sold the colt in the episode titled "Dream A Little Dream of Me", so they weren't able to use it to shoot the invisible dogs known as "hellhounds" that used Dean as a chew toy.

After Sam was stabbed and killed by Jake, Dean made a deal with the cross-roads demon to bring Sam back to life. But, in return, Dean would have to forfeit his own life in one year's time. He he was told that if he tried to welch on the deal, Sam would die. And Dean, being the protective big brother, could not and would not let his baby brother die in his place.

ok thanks for that!

so, if they still had the colt would dean & sam still use it for the hellhound even though they were invisible & if they did use it will the deal be broken??