my ole 8.75 used a vented retaining bolt for the brake block, my 8.25 and 7.25 both use a solid bolt, as there is a seperate vent tube attached to the housing as a vent. If you use a vent rather than a solid bolt, it won't hurt things, but don't use a bolt, where a vent it needed. jUst check your rear for the seperate vent. carefull with the vent-bolt.....then strip often....and use neversieze when installing it. that way you won't snap it off in the housing next time you need to disconnect it. Mike