I got some rear discs from Discovery Auto Parts and the calipers are rusted to hell. They have a 90 day warranty so I figure I could tell them they're seized and get a different set. They look like they aren't functional, but is there anyway of telling without installing them or just making them seized to be sure? Iknow it's kinda dishonest, but the calipers look dangerously rusted.

 

if the piston wont move they are seized.

just rebuild them if you dont feel good about putting them on as is , not like its hard or expensive.

FYI - ALL calipers rust , its where the rust is thats more important.

 

Well the rust is everywhere, there's an extremely thick coat of it all over the outsides and the bracket. It looks like it's been sitting outside in the rain for 5 yrs, which it probably has.

 

thats just cosmetic.

I highly doubt what you are concerned with will affect performance.

just wire brush them and it will come off , then flat black them and forget it.