what's the difference?
 

what's the difference between the front and rear bulk head? they look the same to me. are they interchangeable?

What rc are these bulkheads for?

For the most part, front and rear bulk heads are not interchangable. They ahve the same job, they are just different shape.

emaxx

the rear has no kick-up angle like the front has. and on the rear the caster cannot be changed i think.

i just broke my rear bulk head. can i use my extra front bulk head for the rear?

you cannot do that, the truck would handle rediculous.
it woulnt fit either cuz of the kick-up. the skid wont fit

Compare and contrast:

https://buytraxxas.com/product_info....b0cfc6426b72ad
Front

https://buytraxxas.com/product_info....b0cfc6426b72ad
Rear

Nope, not interchangeable, but they are very cheap to replace- or you can get some aftermarket alloy ones from FLM or GARC etc ( there is a list of great suppliers at http://beatyourtruck.com/links.html ).