Clunkers are Boots or shoes that are too large for the persons foot and they essentially clunk when a step is taken. If your toes are and inch away from the toe of the shoe/boot then you are basically wearing Clunkers.
'She tripped over her clunkers because they were too big'
1 'why'd you get shoes too big for your feet?'
2 'There clunkers, i needed big shoes i can walk through mud with. And the Clunkers i don't care about getting dirty.'
1 'That's stupid'
2 'Thank you'