MagnaFlow exhaust drone

[Ijg4503]

Hello fellow ZR2 owners....... Looking for your advice. My situation: The previous owner of my ZR2 installed a MagnaFlow muffler and removed the flapper. The truck has a VERY annoying drone at mid to highway speeds and it is bad enough, that a lot of times Siri cannot understand what I say when I use the hands free talk to text. Any recommendations to help eliminate the drone (the stock resonators are still there)? I will not invest in an entirely new exhaust system on this truck.... especially with the 6.2L issues, transmission chatter, and recent various recalls. Some ideas/options: 1) Find another aftermarket muffler that will not create the drone, any suggestions would be much appreciated! 2) Find someone that is selling just the OE muffler & flapper assembly. 3) Purchase the right side exhuast pipe assembly that includes the OE muffler. Per my local dealership, the muffler and collar only GM Part # is 85537498.

Any help/advice would be appreciated!

Jason

 

[AXE]

That's not the Magnaflow system that is designed for the ZR2 6.2L motor. It is a generic muffler that can be welded into any exhaust system. The Magnaflow system has a separate resonator parallel with the muffler in addition the stock resonaters. I have a detailed thread on that system I bought from Hottexhaust.com for $600. It'll slpice right in if you remove that can you already have

I think others have posted about the Borla touring muffler that will replace that one. It's less aggressive sound.

 

[TexOffroader]

Another thing that worked for me was to install a 3rd resonator after the cat just before the muffler. I had terrible drone in the cab from my Borla Atak (despite Borla advertising my muffler as no drone, LOL) and just couldn’t tolerate it any longer. I also have the flapper eliminated. I think the stock resonators are too close to the tips to make much of a difference in the cab. Cost me under $200 parts and labor. I did loose a little rumble during cold starts and lead foot driving but I am much happier in the cab.

 

[MAXIMUS]

Another thing that worked for me was to install a 3rd resonator after the cat just before the muffler. I had terrible drone in the cab from my Borla Atak (despite Borla advertising my muffler as no drone, LOL) and just couldn’t tolerate it any longer. I also have the flapper eliminated. I think the stock resonators are too close to the tips to make much of a difference in the cab. Cost me under $200 parts and labor. I did loose a little rumble during cold starts and lead foot driving but I am much happier in the cab.

I’ve got this same setup too. What resonator did you get to eliminate the drone?

 

[TexOffroader]

I’ve got this same setup too. What resonator did you get to eliminate the drone?

Just posted a similar response on another thread. Local muffler shop had a used GM resonator that came off another vehicle. It does not have to be the same resonator that GM installed on the ZR2. Find a local muffler shop around you and they can advise assuming they’ve dealt with drone before. My guy was confident before starting the work and he was dead on.

 

[MAXIMUS]

Just posted a similar response on another thread. Local muffler shop had a used GM resonator that came off another vehicle. It does not have to be the same resonator that GM installed on the ZR2. Find a local muffler shop around you and they can advise assuming they’ve dealt with drone before. My guy was confident before starting the work and he was dead on.

Roger that. Thanks for the advice.

 

[Ijg4503]

Hello Gents, a follow up to my last post. I ended up buying the Magnaflow 19534 | Chevrolet Silverado | GMC Sierra | 6.2L with factory duals only | Direct Fit Muffler Replacement Kit with No Drone Technology from Hottexhaust.com (MagnaFlow). It was $545 shipped. It did not fit exactly per the instructions. I had to cut more off the stock exhaust for it to fit. The over the axle section was a PITA to get the MagnaFlow pipe to fit over the stock tube. Lots of grinding and massaging, lube, cussing, etc. to get it to slip over. Overall it sounds good and has the rumble. The exhaust note is a little louder than I would prefer while cruising on the highways, but the drone is gone! Thanks for the advice AXE!

 

[AXE]

Hello Gents, a follow up to my last post. I ended up buying the Magnaflow 19534 | Chevrolet Silverado | GMC Sierra | 6.2L with factory duals only | Direct Fit Muffler Replacement Kit with No Drone Technology from Hottexhaust.com (MagnaFlow). It was $545 shipped. It did not fit exactly per the instructions. I had to cut more off the stock exhaust for it to fit. The over the axle section was a PITA to get the MagnaFlow pipe to fit over the stock tube. Lots of grinding and massaging, lube, cussing, etc. to get it to slip over. Overall it sounds good and has the rumble. The exhaust note is a little louder than I would prefer while cruising on the highways, but the drone is gone! Thanks for the advice AXE!

Mine fit pretty well, but the photos on the instructions weren't too great. I ended up cutting mine a little short on the section over the axle. Then I found clearer instructions on their website with colored photos. I could then see the cut line better. Once I got it cut right, the install was pretty simple.

The exhaust sounds great and it does get a bit more deep as it is used and the packing wears. Mine is 18 months and it sounds great rolling on and downshifting with the paddles. I will say, you can hear it all little more now in the back seat. Not bad and I don't hear it with radio on, but when I'm on a call or talking to passenger. Not really a done, but you hear the exhaust. I can kill the noise totally in L8 at any speed if I want.