Originally Posted by gabrieldy
That is not true because all your O2 sensors are before the Y-pipe. You aren't messing with anything emissions related because it is after the cats....just helping out the flow. You have as much a chance of throwing a code from changing your Y as you do from changing your muffler. I did mine about 6-8 months ago and no problems at all.
I think if you lay under your truck for a few mins it'll make sense.
Did you notice any difference in changing out your Y-pipe?