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I got an aftermarket, but bigger than the one I had before.
Still cheap, $100
I think I'm currently the world record holder in changing the cat out! Baught it at a shop 3 miles from home. Got home, removed the old one, cut off the flanges, welded them on the new cat, mounted it, took an emission test in another shop nearby and back to the guy who sold it in less than 1 hour. He paid $20 for the bad one...so $80 in total for the new cat
HC down in the 30 ish!


If you can find a stock one that is still good, pick it up for the $20, chances are by the next test the new one wont be working as well.

I put a hi-flow magnaflow on my truck in '04 after I rebuilt the top end. It past in '05, but the HC's & CO were much higher than any test in the past. In '07 it failed the first attempt for idle, everything else was fine, adjusted the idle and it barely passed. This month it failed again, not the HC's but the CO was .05 too high. I put the old oem cat back that had been sitting outside exposed to the elements four 4yrs on and retested it, and it passed w/o issue. The CO was 70% less, and the HC's were 45% less.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed