EXHAUST
The LBMC is used for heavy hauling and daily driving, so the next order of business is exhaust. With an exhaust system, we're looking to improve fuel economy and lower EGTs. Not to mention add some attitude with improved looks and sound.
For this truck, we chose BD Diesel's X-Hale stainless steel dual exhaust system. It's a turbo-back system that is made with 4" diameter 409 stainless steel tubing. It comes with a polished 304 stainless steel muffler and 5" diameter polished stainless exhaust tips. The tubing is seamless and mandrel bent. This is one of the highest quality exhaust kits we've seen. The tube sections fit together well, the hangers were in the right places (except the one that was supposed to match up with the bracket that was moved during the long bed conversion), and all necessary hardware was included. This exhaust system mounts to the elbow on the back of the turbo and goes back from there. We chose to eliminate our catalytic converter (local emissions testing will pass without it in place) along with all of the stock pipe. In order to accommodate the longer length of the LBMC, we relocated one of the exhaust hangers from a section of tube behind the muffler and welded it to the "Y" tube that comes out of the muffler. BD supplied an additional section of tubing that we cut in two and added between the "Y" behind the muffler and the sections that arch up over the rear axle. The rear sections can be pivoted to allow proper alignment of the dual pipes. We also cut about 3-4 inches off of the end of each tailpipe to keep the tips tucked neatly under the truck.
When using the truck on the road in all conditions-empty and towing heavy-we were happy to find that there's absolutely no exhaust drone. The exhaust has a clean, smooth tone that is actually pretty quiet for aftermarket exhaust. For the drive-through windows that the truck will actually fit through, you can still order without having to turn off the engine! When you get on the throttle, the truck makes a deep and muscular sound as it accelerates without being too loud or obnoxious. We also like the fact that the exhaust comes from both sides of the truck. When the windows are down, you hear an even tone from both sides, rather than a stronger tone from the passenger side. With this exhaust kit, EGTs are lowered by 150 degrees on average and fuel economy is increased about 1 MPG.