Flo~Pro 664NM Aluminized 5" Downpipe Back Exhaust | 11-15 GM 6.6L Duramax LML

Flo~Pro 664NM Aluminized 5" Downpipe Back Exhaust | 11-15 GM 6.6L Duramax LML




  • 5" downpipe back system
  • No Muffler
  • Aluminized
  • Single side exit
  • Requires Race Tuning
  • Fits 11-15 GM 6.6L Duramax w/ V-band flange at Downpipe

* Required Fields



Flo~Pro exhaust has been manufacturing and distributing only the most durable quality mufflers and exhaust systems for your vehicle. Flo~Pro has proven that it beats the competition with a louvered pipe that accelerates the exhaust flow through their mufflers. Flo~Pro performance mufflers are designed to boost the horsepower generated from your street vehicle.

Flo~Pro Manufacturing - The inside look!


  • CAT & DPF Delete
  • Exhaust Type: Downpipe-Back
  • Exhaust Tubing Material: Aluminized Steel
  • Exit Configuration: Single
  • Main Tubing Diameter: 5"
  • Exhaust System Sound: Moderate


  • Product Will Not Ship To California
  • Included: Exhaust, Clamps, and Hangers


5 Item(s)

per page
  • Over All Rating

    By Johnny Moore on 10/20/2016

    wish that it come out like the factory

  • Over All Rating

    By Shawn Redmond on 10/19/2016

    Recently purchased this exact exhaust for my 2011 lml the exhaust was shipped fast and safely to me. Install was a snap. The longest part of it and most frustrating was removing the DPF/SCR unit and the DOC filter up by the trans but besides that that install was a snap and it looks and sounds MEAN!! Awesome product.

  • Over All Rating

    By Hunter Green on 10/18/2016

    If you want a loud badass exhaust for your lml duramax, this is the one!

  • Over All Rating

    By Clayton on 10/13/2016

    Was here on time

  • Over All Rating

    By Michael Feldner on 10/12/2016

    Fits great and sounds great. The instructions could use a little more info they are not quite clear on where the pipes for a CCLB go. Easy to figure out for people that have done them before.

5 Item(s)

per page