This FLO - 871 exhaust system by FLO - PRO is a top - notch 4 - inch downpipe back exhaust for 2015.5 - 2016 GM trucks with LML 6.6L Duramax engines and a 3 - bolt flange at the downpipe. It fits all wheelbase and cab configurations, unless stated otherwise. You can ditch your old OE exhaust and swap it with this high - flow street kit. Like all Flo - Pro exhaust kits, it comes with all necessary clamps, pre - welded contour - bent hangers, and stronger flanges for easy installation. The included high - flow muffler is ideal for street - driven trucks. This exhaust not only looks and sounds great but also boosts mileage, throttle response, torque, and flow while reducing EGTs in your LML. Features include a 4 - inch downpipe back single exhaust, OEM - style 3 - bolt flange, high - flow muffler, available in aluminized or stainless steel, single - side exit, and easy installation on OE hangers. Note that it only works with the 3 - bolt flange style off the turbo direct pipe, not the V - band style on some older Duramax trucks.

Using this FLO - 871 exhaust system is straightforward. First, make sure your truck is a 2015.5 - 2016 GM with an LML 6.6L Duramax engine and a 3 - bolt flange at the downpipe. You can easily take out your old OE exhaust and replace it with this kit. The package comes with all the clamps, hangers, and flanges you need. Just follow the normal installation process and mount it to the existing OE hangers. When it comes to maintenance, check the clamps regularly to make sure they're tight. If you choose the aluminized steel option, it's a good idea to keep an eye out for any signs of rust and clean it occasionally. For the stainless - steel version, it's more durable, but still, a simple wash now and then will keep it looking great. And remember, this kit only works with the 3 - bolt flange style, so don't try to fit it on a truck with a V - band style clamp.