1. Welcome To GMTruckClub.com!

    The #1 Chevy Truck Forum Online
    Online since 2004, we are the #1 Chevy Truck & SUV forum and user community. If you have any questions about your Chevy or GMC Truck, SUV or Crossover, or just want to connect with other GM owners and enthusiasts around the world, you've found the best place on the internet to do that.

    Join Today ~ It's Free
    Registering is Free and Easy! Hope to see you on the forums soon!

Which muffler should I get? Flowmaster or Magnaflow

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by slimcubby, Feb 22, 2012.

  1. slimcubby

    slimcubby New Member

    Hey guys,

    I have a 2010 Silverado 5.3L V8 that I want to change the muffler on. I want something with a better tone but not crazy loud. I'm looking to get better performance/MPG out of it. What would you recommend?

    - Flowmaster Delta 50 Series
    or
    - Magnaflow 12589 22" Series
    or
    - Magnaflow 12259 18" Series

    Thanks!
    Slim
  2. mfleetwood

    mfleetwood New Member ROTM Winner 1000 Posts

    I'm not sure your going to increase your MPGs/performance much, if any, by changing your exhaust but you will definitely get a much better sound. From posts I have read, Flowmaster and Magnaflow seem to be pretty comparable. Neither are too loud and most give that deeper tone that many of us are looking for. I have the Magnaflow (forgot which series) but am extremely happy with the sound. It has a nice rumble but can sound pretty aggressive when I put my foot on the pedal. However, with the Magnaflow, some experience a drone type sound at steady speeds on the highway. For me, my tires humming or my music playing keep me from noticing the drone-type sound.
  3. slimcubby

    slimcubby New Member

    Nice. I think im going to go with the 18" Magnaflow. Anybody experience droning with the Flowmaster?
  4. aloxdaddy99

    aloxdaddy99 New Member 1000 Posts

    Did you just swap out the muffler or did you get a complete cat back?
  5. donyms

    donyms Active Member ROTM Winner 1000 Posts

    Well, I'm not an exhaust expert by no means but my experience has been if you want loud and obnoxious go with the Flow-master, If you are looking for a great sound at a level that doesn't wake people up when you drive through there neighborhood then you want the Magnaflow. Also, when I talked to a muffler shop about the differences he said the Flow-masters don't last near as long or have as good of a warranty as the Magnaflow and he sells both. I have the magnaflow for 2 years now and I love it. Also, just a note. If you go with the 1 in 2 out magnaflow instead of the "true duals" it sounds the same and your performance will be better. Just ask any reputable performance shop. Hope this helps.



    More Truck 022rs.jpg
    Last edited: Feb 23, 2012
  6. mfleetwood

    mfleetwood New Member ROTM Winner 1000 Posts

    I did the complete system.
  7. Cheez

    Cheez Member

    I have the Flowmaster delta 50 on my truck. It is a pretty quiet system, with a small amount of extra rumble. There is a small amount of in cab noise but by no means is it a drone. if you're looking for a stock noise level with a different tone I would definitely recommend the Flowmaster.
  8. Jimmeh

    Jimmeh New Member

    The warranty on my Flowmaster matches the same warranty that Magnaflow has on their systems.

    Almost considering making a switch to the 50 series. The 40 is great for being that obnoxious young teenager trapped in a mans body, but on a 500 mile road trip, it gets extremely annoying (then again, my truck has no sound deadening).
  9. MTM

    MTM New Member ROTM Winner

    I'd go with the Magnaflow I think it will be a lot louder and people give to much credit to flowmaster they really don't sound that good they all sound the same. Go with something that will make your sound of your truck stand out not be like everyone else and have flowmasters
  10. div4scpro

    div4scpro New Member

    have a 97 K1500 ext cab with stock 5.7 engine. needless to say was shocked when i priced a new bolt in stock muffler. did some research, a lot of agonizing, and decided on putting a Magnaflow 12580. This is the muffler that comes with the cat-back system for my truck, but didn't want to lose any low end power by going to larger pipes and losing any exhaust velocity and scavenging as 90% of my driving is everyday at 2000-2500 and light trailer towing. well I couldn't be happier. This muffler has exactly the right dimensions to match the dual in, single out configuration that my system has. The volume has not increased one bit no matter how hard I romp down on it, and the only noticeable change is that the exhaust tone, while not any louder, might be just a little deeper, sounds sweet. don't have a computer on it except for seat of the pants, but it does seem that the low end response is a littler bit crisper. all I know is that David at Potranco Automotive did an outstanding job welding the new muffler in place, i worked on aircraft for 30 years and his welds look as good as anything I've ever seen, and out the door for 170.00 for the muffler and the labor is about one third of what the stealership wanted for the same job. I can easily recommend this muffler for anyone looking for something to replace the stock one and not get rocks thrown at them driving through the neighborhood and for a muffler that looks like it will easily outlast the rest of the truck. Andy

Share This Page