ACDelco PF2057 rust?

[caoko]

Got a box of PF2057 filters a few years ago. Been using the filters with no issues, but noticed these two filters have a lot of this brown "rust". The other filters had this too, but was much smaller. I always thought it was some glue or sealant, since there a ring of that right above it. But this looks like rust. Is it rust?

 

[martinq]

Looks like it could be rust from condensation. Maybe old stock that was stored in a non-conditioned space?

 

[ZeeOSix]

Yep, rust ... where were these stored for the last couple years? Humid where you live?

 

[papang]

Clean it up and you should be good

 

[bullwinkle]

Good news is, they won’t rust any more after they’re installed! This is why my spare filters are in the attic & not my (non-heated nor A/C) garage!