AFE Power Large Bore-HD 4" Downpipe Back Stainless Steel Exhaust System

2011 - 2015 6.6L GM Duramax LML

SKU NWD-49-44032


The Large Bore-HD race down-pipe back exhaust system removes exhaust restrictions for maximum performance.

This free flowing exhaust system outflows the factory exhaust by 67% and is constructed out of durable 4" mandrel bent 409 stainless steel and uses bayonet style hangers and band clamps for a clean installation.




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  • Vehicle Fitment

This system also requires an aftermarket electronic module to work properly with the vehicle.

This system comes complete with all tubing, muffler, bayonet hangers, band clamps and is finished off with a high luster polished 304 stainless steel, rolled, slash cut tip. You will be shocked at the performance you will see from this system.

Notes: This is a "Race Only" product used solely for competition. Its use is limited to closed-course racing that is formally sanctioned by a recognized racing organization. Any other use, including recreational off-road use, could be in violation of local, state and federal laws.

*This kit will only fit 2015 models manufactured before July 2014 equipped with a non-flanged down pipe.

All aFe exhaust systems are engineered and manufactured in their Corona, California manufacturing facility.


2011 - 2015

GM Duramax

6.6L LML