MBRP Exhaust Drone

[dieseldavem]

I've got a turbo back 4" MBRP exhaust system with the CAT delete. I'm experiencing a drone in the cab around 2100RPM. MBRP offers a resonator which I've purchased and will install shortly. Has anyone else experienced similar issues?

[draaronr]

Originally Posted by dieseldavem

I've got a turbo back 4" MBRP exhaust system with the CAT delete. I'm experiencing a drone in the cab around 2100RPM. MBRP offers a resonator which I've purchased and will install shortly. Has anyone else experienced similar issues?

yes i have it as well with the same system let me know if that takes care of it, and how it affects the rest of the sounds.

[dieseldavem]

I've also sent an email to MBRP asking about an installation kit for the resonator. Looks like the Excursion kit, although advertised as a 4" turbo back is actually a smaller size for the turbo down pipe and the extension piece that bolts up to the turbo down pipe. On my kit, there's another section of tubing that steps up the size to the 4" diameter of the muffler inlet and has a slight turn to the left if facing the front of the vehicle. I can use the existing transition piece by cutting off a section of the tubing that attaches to the turbo down pipe but I'm afraid that the left bend will kick the muffler too far to the left for the existing hangers. I'll keep you posted. By the way, MBRP says this is the first time they've heard about any harmonics (drone) with their systems.

[Dvldog458]

I have the same system for my Ex. with the cat delete. I did notice a drone also.
I recently deleted the muffler and it is really noticeable now......but it's growing on me and sounds kinda sweet. The turbo whistler is much louder also.

[draaronr]

Originally Posted by Dvldog458

I have the same system for my Ex. with the cat delete. I did notice a drone also.
I recently deleted the muffler and it is really noticeable now......but it's growing on me and sounds kinda sweet. The turbo whistler is much louder also.

i like the whistle but with the family on trips the drone is super annoying,

[Dvldog458]

Yeah... I could see that being a pain.
I also undercoated the hell out of Ex with 10 cans or so of 3M undercoating and bought some Herculiner bed coating and used it on the wheel wells....it helped alittle. Just something to consider if the drone cant be removed.

[FAMILYRIG]

I highly recommend the FTE Resonator. I just had it installed on my Dodge with 5" exhaust. Amazing how quiet it is in the cab while still performing.

[dieseldavem]

Well folks, I got the MBRP 1009 resonator installed today and there's a significant reduction in cab noise. You can still get a harmonic during certain RPM ranges while under full throttle but it's not offensive. To add the resonator, you will need a piece of 4" tubing approx. 1 foot long. I installed the resonator in front of the existing muffler. You will need to cut off the 3.5" to 4" transition piece to hook everything up but make sure you cut the 4" section long enough to get the slight bend. You will need this to tweak the position of the rear section of the exhaust to keep the tubing off of the right rear shock. Required tooling for installation is limited to general hand tools and a saw capable of cutting the 4" diameter tubing. A band saw works nicely.

MPRB provided info on which resonator to use but did not even respond to my email when I asked them about an installation kit.

[Wed Turner]

Do you think that if you had left the cat on the truck it would effect the sound a bunch?

[dieseldavem]

Originally Posted by Wed Turner

Do you think that if you had left the cat on the truck it would effect the sound a bunch?

Yes, I believe it would. The catalytic converters look very restrictive as compared to the straight through MBRP components. The only muffling component of the MBRP products is a series of small scoops cut in a spiral pattern. This perforated piece is surrounded with steel wool.