Just got my new 4" exhaust, turbo back. Looking at the exhaust, I can't tell which way it should be installed. If anyone out there can please help me. The dimples inside the straight thru exhaust are rough in one direction and smooth in the other direction. Which way should I put it on? Thanks in advance

 

It doesn't matter which way it goes.

 

On my MBRP instructions, the only thing it said about the muffler was that if you point the raised portion of the dimples towards the tip, more noise outside, less in the cab. Visa versa if you point the smooth side towards the tip. I opted for the less cab noise but like kwik said, it doesn't matter as far as performance goes.

 

Thanks for the response. I also prefer the noise go outside instead of in the cab, so that is the way I will go.

 

I asked Mark R this exact question when I ordered my 5" system and he stated that I should install it per the arrows on the muffler (muffled dimples facing inlet) or just get a straight pipe. Made sense to me.

 

Thanks. I didn't see any arrows on the muffler which caused me to ask the question. My first time doing this.

 

the direction that would "catch" the airflow in the dimples really quiets the turbo noises. of course i didn't want that, and i put it smooth side towards turbo. now it's sitting on the upper deck in the shop.

 

save yourself the trouble of all that muffler bs and straight pipe that rig
not that much louder but you'll love the sound

 

agreed! the muffler lasted about a week until i heard my buddys straight piped truck. then i took it off

 

Is there a good place to get a muffler delete pipe for the 4 inch MBPR I have looked on Xtreme Diesel but could only find SS for the Dodge and I have aluminized.

 

www.blackclouddiesel.com is where i got mine

 

Thanks Muktown got it on order.