My '02 Tahoe has had SES light going on and off for a few months with code P0420; I swapped out O2 sensors, replaced plugs, and checked for coolant leaks--everything appears to be good--I'm burning about a quart of oil every 2,100 miles, which is acceptable to GM. I'm now faced with having to do CA smog, so I ran the hoe to the dealer. They're diagnosis is replacing converter assembly (inefficient left side converter). The converter y-pipe alone is $2,700, plus tax, plus labor. So, times they are tuff, and considering going aftermarket only for the one bad cat. I've called around to a few muffler shops and they've all told me that CA approved aftermarket replacements are limited to only two manufacturers--Magnaflow, and Walker. Magnaflow seems to have the better reputation. I figure I can do a temporary $300 fix for a few months while I put the money together to do it right with OEM. Anyone else tried any aftermarket cats in CA?

 

I've used Walker in my Honda Accord. Been about six years and no problems. Cost was less than 300.00. Dealer wanted way north of 1000. I would just put in after market. You can put in 4 or 5 after market for that price. Walker came with a five year warranty. Doesn't mean much unless you can prove the car was in perfect tune for that five years or they will blame you and not cover it. Probably the same for the dealer.

Tom