MBRP 4" PLM Series Downpipe-Back Exhaust System S6004PLM

2001-2007 GM 6.6L Duramax (All Crew & Ext. Cabs) (Off-Road)
✔ QuickShips by Next Business Day*
MBRP Performance Exhaust
XDP Part Number:
$5 Price Beat Guarantee
XDP - MBRP Authorized Online Retailer XDP is a MBRP Factory Authorized Online Retailer ID# 600207727. We would like you to shop with confidence knowing your purchase is covered by the manufactures warranty.   

The Best Systems Start with the Best Materials

Built from heavy duty aluminized steel our PLM Series exhaust systems offer a value price without compromising on the quality built into every component. While the seams are a major point of rust through with some budget systems our fully sealed tubing adds years to your system. Constructed to the same specifications as our top of the line Pro Series we back this line with a 1 Year Warranty.

Built to Perform
You count on your truck to tow all of your gear to where you want it. With your MBRP performance exhaust you can make that happen with up to18 HP more horsepower and 28 ft/lb more torque. Give your truck more pulling power and much improved throttle response with an MBRP diesel exhaust system. Our systems are so much more efficient, it will be easy to see what your truck can really do.

Minimize Backpressure

The secret to getting more out of your diesel engine is to give it lots of cool, clean air. The only way that you can get fresh air in is to get the hot air out. From the spiral louvered high flow muffler to the fully mandrel bent tubing to minimal bend degree angles, your MBRP performance system gets exhaust out fast. Drop exhaust gas temperature by up to 200ºF and set the stage for all the performance you want. An MBRP performance exhaust system is the starting point to getting the most from cold air intakes, programmers, modules and downloaders.

Easy Installation
MBRP systems are as much fun to install as to drive with on your truck. Bolt-on, no weld design makes installing this on your truck a no hassle one and a half to two hour project. Everything is direct fit to the OEM hangers and you get all the clamps and parts you will need, all in one box, no matter what configuration of truck you have.

Sound & Style

Performance is one thing but at MBRP we believe that appearance and sound is just as important. Every MBRP performance exhaust system has been specifically tuned to get the optimal sound from your pickup. With our MBRP brand etched on the tip and our unmistakable styling, there's no question that you have the hottest exhaust on the road - MBRP.


  • 4" Aluminized Steel Construction
  • Downpipe-Back Exhaust System
  • No Muffler - "Straight Pipe"
  • 1 Year Warranty
  • Installs With Common Hand Tools
Regular Cab's Require Adapter Pipe Below.

Application Note:
All Cabs & Beds applies to GM 2500HD/3500HD Pickups. This system is not designed for use on Cab & Chassis models.
Mfg. Number:

Customer Reviews - Include your order number for a chance to win a $100 GiftCard

(36 Ratings, 4 Reviews) Average Rating:
Overall good exhaust, great sound
Paul (Arkansas) 2/25/2017 11:08 AM
Easy bolt together. However, my hangar didn't align on muffler delete pipe. Thankfully had the extra clamps for extension pipe otherwise would have been hosed. The MBRP instructions while ok should be a touch more detailed, better photos. Too minimal. Nice look, nice sound. Cabin drone until you get to speed, but then it almost completely goes away. 4 stars for now!
Great Product
Beau (Troy, MO.) 7/21/2014 1:18 PM
Put this on my 04 LLY. Very easy to put on. Goes better if you have 1 or 2 extra sets of hands. Some guys said you could remove the whole factory exhaust without cutting it up (think by lifting the rear end up?) but I just used a sawzall on mine to cut it in half. Truck sounds great now. It's not terribly loud while idling, especially if you're on the driver's side, but whenever you get on it, it's loud. Does have some drone while at highway speed, but you don't have to turn the radio up too much to cover it up. Hard not to go between buildings now and not hit the accelerator. Improved my fuel economy by 1-2 mpg also, as well as keeping the engine a tad cooler. I'd buy it again if I had another truck.
Worth every penny
Justin (Lander, WY) 4/5/2013 12:06 AM
This system is insanely loud when under load. I now have one of the best sounding LB7's around. Installation is fairly strait forward. Removing the inner fender on the passenger side to remove the front pipe from the down pipe makes getting them apart and the new one on much easier. Just quit thinking about it and buy it, you won't be disappointed.
Easy install
Matt (WYO) 12/26/2010 10:39 AM
Great easy product to install. Took me just a few hours of taking the stock out and putting this in, even without a lift. Sounds awesome with a 5" tip.