Actually all the nissin calipers use the same small parts...pins, sliders and rubber pieces. You can use any year 300 and 400 ex, the calipers havent changed for them, since they were new. Ronnies breaks out the small pieces for the hondas, but not the suzis or yamis. Im not sure why, but i know the parts are the same.

 

Gotcha. I just looked up the rear caliper for a 2003 400EX....looks like part #16 will do the trick?

 

Yep, And if you look at both the 300 and 400 front calipers...its the same part number.

 

Excellent. Thanks so much for helping me out. I'll finally have a 100% functioning rear caliper once I order that part.