Re: 5in down pipe?
I helped a friend put a 4 inch one on his 6.0 and it was really tight, you'd be hard pressed to fit a 5 inch without modifying the firewall like stated above
'05, CC, SB, 4X4 6.0L, Studded, EGR Delete, Warren 175/50's, Garrett Powermax, S&B intake, MBRP 5" straight pipe, SCT w/custom tunes from Innovative. Dyno'd 590hp/1019tq<-----Moved on
'15, CC, SB, 4x4, 6.7L........bone stock
Amateurs will practice until they get it right, Professionals will practice until they can't get it wrong.