MBRP exhaust question

[Mcheil83]

I have a 2015 Sierra 2500 gas 6.0 ( I have no carpet, factory vinyl floor ) and recently installed a MBRP Cat Bak exhaust and holy cow I have serious drown on the highway at cruising speed. I’ve read reviews about this MBRP system an a lot of people said the drone was not bad at all.  Anyone else have any similar problems? Thanks Matt

[avalonandl]

You need to put some sound deadener under your vinly floor. The Mat stuff. Will quiet down the drone.

[Mcheil83]

I’ve been up most of the night doing a ridiculous amount of research an was thinking about installing the helmholtz resignator, any one ever hear of this?

[avalonandl]

Yep, a J pipe. It works.

 

Which rpm is the drone at?

[Mcheil83]

2000 rpm cruising on highway. you wouldn’t happen to have a pic of how you did it, dimensions how long you made your tube? I know  once we pull our camper the drone is going to be ridiculous . Thank  soo much

[paauto]

On 3/7/2019 at 9:14 AM, avalonandl said:

You need to put some sound deadener under your vinly floor. The Mat stuff. Will quiet down the drone.

 

Totally agree.  I pulled my seats and carpet out and laid Dynamat on the entire floor/back wall/B&C pillars as well as heat insulation.  Very quiet truck now.

[avalonandl]

On 3/8/2019 at 11:24 AM, Mcheil83 said:

2000 rpm cruising on highway. you wouldn’t happen to have a pic of how you did it, dimensions how long you made your tube? I know  once we pull our camper the drone is going to be ridiculous . Thank  soo much

I have not installed j pipe, just know they work if designed right.

[Big Whiskey]

The 6.0 is notorious for drone with aftermarket exhaust. That's the only reason I haven't changed mine. I really like how quiet it is while cruising and I don't want to ruin that. My suggestion would be to change the muffler or add a resonator.  

[gearheadesw]

I've  had trucks with exhaust modifications, and in the end hated the sound. Every little hill, roar, every little hit on the gas, roar, every little acton on the gas pedal, roar, the load pedal after exhaust. No thank you any more.

[EXSlider400]

22 minutes ago, gearheadesw said:

I've  had trucks with exhaust modifications, and in the end hated the sound. Every little hill, roar, every little hit on the gas, roar, every little acton on the gas pedal, roar, the load pedal after exhaust. No thank you any more.

Almost same here. My new vehicles keep the OEM exhaust  (Duramax HD and E550 AMG) as we use them more often and for longer drives. My older one (2007 Sierra) has a stainless round Magnaflow that was put on in November of 06 and still sounds decent with over 300k miles...my 1967GT 289 sounds much better but...just long tube headers and flow masters with h-pipe. I have hear the J-pipe works for drone though   

Edited March 19, 2019 by EXSlider400