greenhornet
Full Access Member
Back in 2015 my Tahoe had the droning at certain speeds.I took it to the dealer to check it out and they replaced the cat back pieces with a new updated system .The old pipe had a easily fixed flapper valve with a bolt to lock it open.The new system has round knob that will rotate but no way to lock it open.It rotates with a pair of pliers but no idea if it is open or closed, just stiff enough to not bounce back. Anyone come across this setup or how to lock it open as V4-V8 is disabled.It is way to crappy out to get a picture at this point,snow,slush and freezing out.