Magnaflow cat converter and catback system and O2 sensor question

[mntn-biker]

I've been throwing a P0420 code lately on my base model 2003 FWD with ~148,000 miles. I can drive around town without throwing it but get out on the highway at 75mph for an hour or more and the check engine light comes on and it's the same code. I'm guessing my catalytic converter is failing since at higher rpm's for extended times, the cat would get hotter? Anyway, been looking at the Magnaflow catalytic converters since I've been told they have better flow than OEM. Anyone been down this road before? I am seeing 2 different part numbers. 1 looks like it is just the catalytic converter without the header flange mount or trailing pipe with the O2 sensor mount:

http://www.magnaflow.com/02catalytic_co ... rsal=51205

The other part number looks like it has from the flange mount back and includes the resonator???

http://www.magnaflow.com/02catalytic_co ... tfit=49461

Then looking ahead, I'm thinking the exhaust might not be too far behind and see the Magnaflow catback system has a resonator included?

http://www.magnaflow.com/02product/disp ... mber=15759

Also wondering about replacing the O2 sensors while I'm at it? Think I read on here that there are a couple of them to replace?

[vibenvy]

Just wanted to recommend Hott Exhaust for any Magnaflow parts you may need. Be sure and use the link "Get Coupons" on their homepage. Tell them what part/s you're wanting and they'll send you a coupon code to use to save a ton of money. They also offer free shipping.

[mntn-biker]

Just wanted to recommend Hott Exhaust for any Magnaflow parts you may need. Be sure and use the link "Get Coupons" on their homepage. Tell them what part/s you're wanting and they'll send you a coupon code to use to save a ton of money. They also offer free shipping.

WOW!!! Thanks for the heads up on that coupon VibeEnvy! That'll be a huge savings when I go to order these parts!!!

[vibenvy]

You're very welcome !

[mntn-biker]

Looks like HottExhaust has their own branding of the tubing since I see a 3rd option for the catalytic converter assembly with their description "Magnaflow Core-Hottexhaust Tubing"? This 3rd option is even cheaper yet for the cat

[lannvouivre]

The Magnaflow cat includes the primary cat converter and the secondary cat. Further back is the third bulge (resonator). Neither of these Magnaflow kits includes it.