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Flowmaster 40 Series Delta Flow Mufflers Customer Reviews

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51 Customer Reviews

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Customer Reviews

Mustang Growl !

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Reviewed by Thomas T (Carolina Shores, NC) Reviewed for a 1997 Ford Mustang — 2007-08-15 05:08:14

The flowmasters gave my '97 cobra a very distinctive exhaust note, the " Mustang Growl" I like to call it. The 32V engine combined with the Delta-flow 40 mufflers make beautiful music together.I've owned this car for 3 1/2 yrs, and I'm sorry I waited so long to replace the stock mufflers. Thanks Flowmaster !

What a difference!!

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Reviewed by David L (Jacksonville, FL) — 2007-03-16 05:41:38

I started with the 50 suv series on my 03f150 w/4.6L which also has a K&N intake, Throttle body spacer, and edge programmer. Now it sounds much more throaty. Interior resonance is definately increased but not to the point of annoince. I rate the muffler w/5stars but they sent me the wrong one. I ordered 2.5I/O and received 2.5I-2.25O. Shipping was super fast, Just wish I got what I paid for.

nice sound

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Reviewed by todd ` s (Kittanning, PA) — 2008-04-08 22:18:19

this 40 series has a very nice external sound but does get loud on heavy throttle. interior resonance is a bit more than anticipated on pullout but very minimal at cruising speed.

08 Tacoma w/Flowmaster 40 Series Delta Flow

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Reviewed by Aaron M (Merced, CA) Reviewed for a 2008 Toyota Tacoma — 2008-04-10 08:47:57

Awesome muffler. I put this muffler on my 08 Tacoma Dbl Cab 4.0 V6. Wasn't sure if i liked the tone at first but like everyone says it works itself in. Sure enough after putting some miles on it, it sounds completely different. Exactly the sound i was looking for. I'm glad i made this choice.

Great mufflers

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Reviewed by khaled a (sabah alnaser, kuwait) — 2008-03-14 07:48:52

I was worried that after installing it on my 2004 crown vic it would create very high noise, but I got an amazing deep cool sound, %100 as what I wanted. it was also easy to install. I am glad I choosed the flowmaster 40 delta flow series. Khaled.A, Kuwait.

What can I say, they're Flowmasters

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Reviewed by cornelio a (Houston, TX) Reviewed for a 2008 Saturn Aura — 2007-03-07 21:18:52

This is the 4th vehicle I've used Flowmasters on, and once again, they deliver. Awesome sound! Best sounding mufflers in my opinion.

Best improvement for the money.

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Reviewed by Scott J. L (Syracuse, NY) Reviewed for a 2006 GMC Sierra — 2008-01-10 04:54:57

Ordered online and saved 50%versus local dealer.Had installed at shop for $60.00. Make sure you get muffler a quarter inch bigger than exhaust so as not to restrict the volumn.Great sound and noticed better all around perf.improvement.Very pleased.

AMAZING!!!

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Reviewed by JEREMY A (Manchester, TN) Reviewed for a 2005 Dodge Ram — 2008-03-25 19:59:57

I JUST INSTALLED MY FLOWMASTER 40 SERIES DELTA FLOWS AND I COULD NOT BE HAPPIER! THEY ARE THE BEST SOUNDING FLOWMASTERS THAT I HAVE EVER OWNED! THERE IS SOME NOISE INSIDE THE CAB AND A BIG GROWL OUTSIDE THE CAB. I DON'T THINK THAT FLOWMASTER COULD HAVE MADE A BETTER MUFFLER FOR MY HEMI.

Flowmaster 40 Series Delta Flow

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Reviewed by Lisa K (Independence, KS) Reviewed for a 1970 Ford F100 — 2007-09-19 17:23:01

These mufflers sound great! They have a mean low growl that isnt to noticeable on the inside..but once you get outside it sounds meeaann!

FloW 40 Delta

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Reviewed by Megan C (Jupiter, FL) Reviewed for a 2004 Chevy Blazer — 2007-07-31 06:34:40

This muffler is off the chain..i installed it on my 2004 Chevrolet Blazer 4.3 V6..it sounds like a V8 in idle and peak power is anywhere from 1500RPMs to 2300RPMs..its a great Muffler!!! i would recomend it to anyone with a blazer..

Great Sound

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Reviewed by John A (Delta, CO) Reviewed for a 2005 Subaru Impreza — 2008-07-25 23:38:43

I put this muffler on my subaru impreza outback sport and man does it sound mean. I went out on a limb when I bought it because I had not found any videos or recordings of flowmaster mufflers on subarus but the sound i got is very satisfying.

Flowmaster 40 delta flow review

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Reviewed by Mickey D (Simi Valley, CA) Reviewed for a 2001 Dodge Durango — 2008-08-08 00:20:33

I really enjoy my new muffler. The sound is awesome, nice deep tone :). makes my 2001 dodge durango look and sound tuff. only thing that bothers me is that they didnt have the muffler in stainless steel but in aluminum, its not that big of a problem though because flowmaster change their warranty to 10 years. but other wise really great product would recommend to anyone.

Flowmaster 40 Series

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Reviewed by John M (Las Vegas, NV) Reviewed for a 2007 Ford Mustang — 2008-05-23 16:49:56

I've had the Flow 40 Delta on my 2007, v6 Mustang for a few weeks now and they sound amazing. They are loud enough on the outside and resonate just enough on the inside to be fun and not give me a headache. I even drove from Las Vegas to Denver without any problems or annoyances. If you are looking for a great muffler with very good sound, go with this one. I searched for months before I settled on the Flow 40's and I couldn't be happier. Also cheap instal and I had a chrome tip welded on that really completes the look.

2005 GMC SIERRA 1500 SLT

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Reviewed by Pawel S (Fort Walton Beach, FL) Reviewed for a 2005 GMC Sierra — 2008-09-16 12:45:12

I love it . That`s what I wanted !!!

very loud!

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Reviewed by jeremy a (San Diego, CA) Reviewed for a 2002 Toyota Tundra — 2007-10-23 22:40:17

I installed this on my 2002 tundra 4.7l. this thing screams!

awesome

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Reviewed by Gregory K (Tonganoxie, KS) Reviewed for a 2000 Lincoln LS — 2006-03-09 21:27:56

They sound fantsatic! had many compliments on them! thanks Greg

new truck

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Reviewed by schon w (Olympia, WA) Reviewed for a 2005 Ford F-150 — 2008-08-14 20:25:57

had straight pipes and was to much for me this was a good sound with out to much

My Bronco came alive!

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Reviewed by Scott W (Ponca City, OK) Reviewed for a 1979 Ford Bronco — 2007-09-11 11:26:50

When bolted on, I could hear and feel a difference over the stock single exhaust. The exhaust was upgraded to a dual system. They say "if you can make a motor breath better, it will perform better"

Growl... for a 4 cyl Ranger

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Reviewed by Evan S (Apple Valley, CA) Reviewed for a 1996 Ford Ranger — 2007-07-27 11:16:36

Awesome agressive deep sound. Loud enough without intake, even louder with. I recommend it to anyone who wants sound that will last. No iternal parts that may break down over the years, just a fat resonating chamber...good stuff.

Great

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Reviewed by Hayden S (Pawnee, OK) Reviewed for a 1978 Ford F-100 — 2012-08-16 21:28:30

Put this on my show truck. Sounds great for a v6! Nice and throaty

NICE

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Reviewed by Michael W (Rancho Palos Verdes, CA) Reviewed for a 1984 Dodge Ram — 2007-07-06 10:05:12

I think that the Flowmaster Muffler 40 Series Delta Flow sounds great on my truck! The truck preforms much better! While it also sonds great! The dual exaust looks great and ads to my truck with great features! Thanx for the product and i look foward to buying more products form you guys!

2009 F150 with a Rumble

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Reviewed by Mark M (Ada, OK) Reviewed for a 2009 Ford F-150 — 2009-09-13 16:52:07

Had my Flowmaster 40 Series Delta Flow installed at a local muffler shop and what a difference!! I used my stock exhaust pipe and reconnected the stock tailpipe as well and am not diappointed. It took just a bit to get used to the markedly increase exhaust note but it sounds great! Very deep tone with just a slight amount of interior resonance around 2000rpm.

SUPER 40'S DELTA FLOW!!!

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Reviewed by Treston S (East Wenatchee, WA) Reviewed for a 1991 Toyota Pickup — 2008-04-10 20:35:08

All i can say, is that everytime i start my truck and take off ; It gives a beautiful mellow sound that puts a huge grin across my face. It was exactly what i wanted, i got the delta flow cuz I didn't want it to be super loud but have a mellow sound. And it matched the sound i was looking for. Also gave better acceleration on highway up hill and don't have to downshift to fourth as quickly. not sure about milage, I love the sound so I kinda have a heavy foot for the gas pedal. all a round its an awesome product and i'm very happy to have purchased it!!!

nice american rumble

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Reviewed by Alex W (East Orange, NJ) Reviewed for a 2001 Oldsmobile Alero — 2012-11-15 12:23:49

had it professionally installed sound better than i could image dont know about fuel eco cause i gotta heavy foot but couldn't be happier

love it

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Reviewed by Klinton V (Belton, MO) Reviewed for a 1998 Ford F-150 — 2009-12-15 20:20:01

got this for my 5.4L f150 and it sounds great with my dual exhaust. totally recommend this for your truck

Flowmaster 40 delta series muffler

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Reviewed by John S (Westminster, MD) Reviewed for a 2007 Chevy Silverado — 2012-03-21 12:51:58

my local muffler shop put it on in an hour, its alot smaller then the stock muffler so i didnt want to mess with it. Has a mean growl on the exterior, with little interior noise, which is the reason i went with this muffler in the first place! I am very happy and would recommed it to anyone! the only thing i would do differently is get the dual outlet for a louder/meaner growl!!

04 Monte Carlo SS DEJ

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Reviewed by Robert H (Warren, MI) Reviewed for a 2004 Chevy Monte Carlo — 2011-04-30 20:10:06

Wow! Great sound. Did a lot of research about mufflers. Placed a call to Flowmaster and told them what I wanted. They were very helpful when I told them what I wanted. They recommended the series 40 for an aggresive sound. Autoanything was helpful also in my decision. Autoanything was prompt on delivery and the price was the best I found after doing much research about pricing.

Sounds great!

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Reviewed by Jason S (Lexington, KY) Reviewed for a 2009 Dodge Ram — 2010-03-30 04:58:14

I have an 09 RAM 1500 and it sound mean as hell now!

Flowmaster Mufflers 40 Series Delta Flow on 04 silverado

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Reviewed by Patrick H (Snoqualmie, WA) Reviewed for a 2004 Chevy Silverado — 2007-04-03 20:45:58

This muffler is badass, adds the perfect agression i needed for my truck, low interior sound, but an agressive loud and powerful sound on the outside, definatly a head turner, this is on my 5.3L V8 it sounds SO GOOD!

Flowmaster 40 Delta

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Reviewed by Matthew C (, ) Reviewed for a 1999 Chevy Blazer — 2013-01-20 10:40:03

Wasn't sure how it would sound on a V6 but all I wanted was something to give it a growl. This is perfect for a V6. It doesn't sound like your trying to get more muffler than you got engine it just a great tone to grab attention. Installation was less than an hour. I put it on a car lift (cheated a little) cut the old one off used small amount of exhaust tubing and a couple clamps and its holding sturdy. Great Deal!

2005 Ram, Quad Cab, 4x4, Hemi

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Reviewed by David C (Conifer, CO) Reviewed for a 2005 Dodge Ram — 2009-08-10 19:06:32

I recieved the muffler in short order and had a local shop weld it into place. The Flowmaster is only about half the length of the original stock muffler, which is the size of a Smartcar....lol. I have not noticed any increases in power or economy, but the sound is the real reason for getting one of these. I originally took the resonator off when the Flowmaster was installed, but this created a loud drone in the cab between 1400 and 2000 rpm. The sound was awesome, but I had to re-install the resonator to quiet the cab down. The tone is still awesome though. All in all, very happy with this product.

Best moderate sound increase.

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Reviewed by Douglas B B (Havelock, NC) Reviewed for a 2009 Dodge Ram — 2012-09-06 13:28:51

I bought the Flowmaster 40 Series muffler not for the performance but for the sound. I went with the Stainless Steel because it seemed to help cut down on in drone inside of the cab. This is the perfect muffler if you want just a bit more clean smooth sounding exhaust.

40 Series Delta Flow - a great compromise

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Reviewed by Brayton G (Walton, NY) Reviewed for a 2003 Chevy Corvette — 2009-04-24 06:11:43

Just what you said. Good exterior sound, less cabin noise. I'm happy.

2010 Ram 1500 Crew Sport 4X4

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Reviewed by Bryan D (Hawkins, TX) — 2010-12-09 17:00:11

At first I didn't like the sound of the delta 40, then I had the resonators removed, WOW, Love the sound of the delta 40. Just perfect for me... not too loud or too soft, sounds awesome when get on it.

Great Flow

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Reviewed by Nick D (Murfreesboro, TN) Reviewed for a 2003 Kia Sorento — 2008-04-27 09:20:49

Great muffler for the price...sounds great and has that deep growl at idle too.

sweet

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Reviewed by Adam D (Muenster, TX) Reviewed for a 2003 Chevy Silverado — 2007-07-20 14:51:24

This muffler is great, very little interior resonace with aggressive exterior growl. I really like me new muffler.

Nice rumble

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Reviewed by James M (Collegeville, PA) Reviewed for a 2004 Porsche Cayenne — 2007-06-29 04:09:54

Installing it was a breeze. I like the rumble of the Delta 40, however, I wish it was a little louder.

Flowmaster 40 series

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Reviewed by John L (Sheboygan, WI) Reviewed for a 1996 Mitsubishi 3000GT — 2008-08-12 01:53:46

Sounded great! Very easy to install and worked great with a dual tip set up. Made my car sound more aggressive and noticeable. Caught a lot of people's attention on the road.

nice soud with better fuel economy

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Reviewed by Jason F (Eagle Mountain, UT) — 2008-04-10 20:36:50

This flow master has a very nice sound not too loud for my wife when she rides inside the cab of our 2004 chevy short bed v8, and I noticed an immediate difference in power and fuel economy well worth the price it would have been better if it cost less but... still worth it!

40 series pleasure

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Reviewed by Leon S (Laurel, MS) Reviewed for a 2005 Dodge Ram — 2006-01-23 20:25:56

The 40 series sounds great on my 05 Dodge Ram 1500 v6. It dows have a slightly irritating sound on hard acceleration, and I have yet to see mileage inprovements. Overall this muffler is still a great sounding replacement for a stock exhaust. @ idle the truck sounds just like a v8. While driving, interior sound is considerably less than the 50 series and allows for a comfortable ride. Enjoy!

Flowmaster 40 series Delta Flow

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Reviewed by John Y (Novi, MI) Reviewed for a 1968 Pontiac Firebird — 2007-08-15 10:14:31

These mufflers sound good outside of the car. They give the car a nice growl. I have a 1968 Firebird with a 400 engine. A little more resonance inside of the car than I expected. I am running 2 1/2" exhaust.

exactly wha I wanted

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Reviewed by Brendan s (Chandler, AZ) Reviewed for a 2004 Ford Ranger — 2011-01-27 20:47:43

I ordered this muffler, and I had it at my doorstep alot sooner than I was expecting. I will definately use this website again. The muffler adds an aggressive tone to my truck, without the annoying cab drone of other flowmasters. Highly recommend!!

Nice . . 8/9 out of 10

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Reviewed by Andrew R (Saginaw, MI) Reviewed for a 2004 Dodge Ram — 2007-06-25 14:55:33

I had glass packs added to my 04 Dodge Ram for inexpensive added exhaust sound. I decided to get the dual outlet Delta Force Muffler to make a change. To really see about the torque/hp added and the clean sound. The glass packs' raspy start was replaced by a real THROATY DEEP sound. Really made it sound like a DODGE TRUCK. Torque gains were noticeable but nothing mind boggling. It was really the deep power sound that gave people walking by, driving by look at what i had going. MPG gains? = None. I didn't see a change at all. At 55mph at 4300 rpms i was running about 24mpg on the comp, but now it's 21mpg. Other constant rates seemed to differ also. Overrall though, i love the sound. Interior is not loud, and that's what I want. U can definitely hear it, it's deep but nothiing too much that will give the headaches.

Nice Sound!

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Reviewed by Hattan M (SARASOTA, FL) — 2011-10-06 11:16:52

The finishing for this mufflers is not that great but the price it focus in the sound.Great sound for the price actually.

40 series delta flow on a 2008 Gmc Sierra 5.3

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Reviewed by Gary A (Alden, MI) Reviewed for a 2008 GMC Sierra — 2010-05-01 06:22:07

Sound level and tone from the exterior are perfect. Inside I have a bit of a harmonic drone around 1700 -1900 rpm range that is a bit too loud otherwise interior noise levels are about what I expected. This is my 3rd Flowmaster on as many trucks I'm sure it won't be my last.

07 chevy 6.0

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Reviewed by chad d (Oklahoma City, OK) Reviewed for a 2007 Chevy Silverado — 2008-02-19 09:13:12

If your'e looking for muffler that doesn't produce alot of interior noise this is the one for you. Still has a nice rumble on the outside but not to loud.

Rumbles

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Reviewed by Tonia P (Kennewick, WA) Reviewed for a 2006 Toyota Tacoma — 2011-12-28 17:04:35

Great rumble

Flowmaster 40 Series

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Reviewed by Matthew S (Akron, OH) Reviewed for a 2000 Honda Accord — 2007-10-16 12:07:07

I ordered two of these mufflers, and they are the best ones that I have come across, they sounds great, and I noticed a little better performance as well.

Flowmaster

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Reviewed by Linda O (Mahwah, NJ) Reviewed for a 1999 BMW 5-Series — 2011-02-07 15:04:11

This muffler is great, dont get me wrong but the representatives did not know a thing about my car, although the said they did. I sent back and order a new muffler that they recomeneded two times before i had the right one. The car sounds great and has a very deep tone to it. Not too ricey at all which is what i was looking for. It has the loudest tone to it at about 2000-2500 rpms. The muffler was extremly hard to install and remember to get it bigger or smaller than the pipe on your car so that it may slide on or in and make it easier to weld. I am decentlt happy the way it turned out. (3.5 out of 5 stars)

silverado

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Reviewed by Shayne M (Kalama, WA) — 2011-02-10 12:53:41

It sounds good. I also put one on my wife's Tahoe and it sounds a little better on their than my Silverado but worth the money.

pussey cat

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Reviewed by Donald P (Dingmans Ferry, PA) Reviewed for a 1998 Dodge Ram — 2006-08-27 15:06:46

was waiting a much more aggresive sound