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So yesterday I finally got around to installing my MBRP 4inch downpipe back exhaust. Its been sitting around the house for awhile I just finally got a nice day!

Here are some pics of what I did.

The full system set up just to ensure everything was there. (since I have an extended cab I didnt need to use the 18inch extension pipe)

I took the rear shock off and jacked up the truck to make it easier to take the muffler and tailpipe off. I pulled it through the front which made it a lot easier.

This is somewhat of a tricky part. Make sure you spray the bolts on the DPF/CAT/MUFFLER with some liquid wrench. I found it helped a hell of a lot. You have to unbolt the little bracket that holds those 2 hard lines, and then disconnect it from the connector. There are also 2 soft wire probes that are hooked up on the frame with plastic screws, just pull them apart and leave the connections there. Any connectors kicking around I just wrapped them up with electrical tape to protect them from the elements. Also you'll have to unscrew the front probe to allow it to clear the crossmember. I believe its a 17mm box end to get that out.

Uh oh, DPF FELL OFF:O:O:O This big hunk of junk is pretty damn heavy. Id say during the whole process of swapping out the exhaust I probably picked up 100lbs of weight reduction.

Took the front wheel well cover off to gain easier access to the downpipe, exhast flange. It made it a lot simpler. when your hooking up the new front pipe if you dont have a second person I would suggest using an axle stand to support the pipe while your trying to get the O-band around the pipes.

I jacked up the front of my truck to be able to take the frontpipe / cat out. It makes a lot more clearance that way you dont have to chop up your exhaust if you want to keep it just in case.

I used a zip-cut to cut 9.5 inches off the extension pipe (because I have an extended cab)

The new exhaust installed. It doesnt use the transmission hanger that the factory one does but thats no big deal as it weighs a lot less.

This is all the crap you have to take off.

Wow that looks so much better than the stove pipe that used to be there. I finished it up then got in the truck and tuned it up with efi live. All Im running now is modified stock tune with the DPF programmed out. As well as a few codes it threw set to NO MIL. Truck has better throttle response, sounds better, and actually smokes a bit when I walk on it.

YouTube - 2008 Duramax with MBRP Exhaust + EFI Live
Just a lil video of it. I hear some people complain about that turbo hiss.. I actually love it. It makes the truck sound like a jet at idle. When you WOT it though it sounds like a mad dog growling all the way down the road. (If you really want to get the full effect click on the video and watch it in high quality on youtube)
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