I didn't think changing muffler would.i have been researching since I got my truck and haven't read one thing about a code popping up.yea stock is horrible. The first week I cut off resonator and opened the muffler valve but didn't help much.
thanx for the quick replies. I was also planing on adding just the airaid tube. I've read good reviews on it with leaving stock air box but got to get my truck from sounding like a 4cyclinder Corolla first. Lol
Yea that's what my dealer said also cause of how the truck is tuned and changing flow and exhuast temps could set off a check engine code and come back on me for the mod. I don't want to mess with cats, even though the third one bothers me just cause it's there,I was just planing on something like southernsilverado guy done.i have had flowmaster before on previous trucks and loved the tone but never gained anything but sound. Any other suggestions? I been looking at magnaflow and borla.