my left cat makes a loud rattling sound in first gear and the cheapest price I could find was either $700 from a muffler shop, or $450 online and I'd have to install it myself. I know they have universal fit cats for like 100 bucks, my question is, are cheap universal cats a bad idea? And has anyone had a problem like this where it only rattles in first gear, then disappears?

 

the universal cats works, just look for the 2 holes for O2 sensors, one is located before the catalityc converter and the other is after it, if your computer donĀ“t send the message "check engine" your cat is still working find