Duffboy8

Hey all. I got a blown rear pass cat on my 05 c55 amg and was wondering if I needed to replace it? Throwing no code. Dealer said I’ll need o2 sensors as well but I remember reading on here before that the rear doesnt have them. Anyone have a good site to get replacement parts? Thanks!

Spooky55

Magnaflow makes CA approved rear cats for the C55. Unless it is plugged or rattling though, why bother?

kaixdiego

if you have one blown and one not, car will be affected flow wise, although it may not not be noticed at first could cause issues down the line. IMO deleting the secondaries is a preventative measure in case the fronts were to ever fail, you would avoid the possibility of primary cat material clogging at the secondaries, causing real issues. Also If the dealer told you that, then don't go back to that dealer lol