We have a new custom exhaust guy in town who is advertising a nerf bar/side pipe dual exhaust. I told him I wanted 4" straight pipe and he told me that with the pipes that short that all his new exhaust info says you lose performance. The pipes would actually end somewhere behind the cab. He suggested staying with the stock 3.5". Anyone heard of this?

 

Uhhh - obviously that guys knows diddly squat about turbo-diesels. You do NOT need any kind of back pressure - your turbo gives you all that you need. Go ahead and open'er up to 5" if you like!

 

im runnin 5" out the side on my truck no performance disavantages.

if your gonna run it out the side why dont you do it yourself?

need
downpipe,
adapter from downpipe to size tubing you want
4-6' of pipe depending on cab and bed configuration
1 45 degree bend
3-4 hangars
nice shiny tip

all stuff you can get at big rig shop

did mine for $300 including tymar ceramic coated downpipe