Flowmaster® - American Thunder™ Exhaust Systems

60 reviews|Item # sp25|Similar Products
$159.95 - $1,579.95
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Product Details

American Thunder™ Exhaust Systems by Flowmaster®. American Thunder gives you the Mild-Moderate Sound / Moderate Sound / Aggressive Sound / Moderate-Aggressive Sound / Mild Sound (depends on application and exhaust type) of a Flowmaster chambered exhaust, which is the classic sound of classic American big performance engines. This is a system that gives the most sedate vehicle a performance rumble. American Thunder is perfect for a wide range of cars, from ponies to sleepers.

Features

  • High Quality Performance Sound
  • Increases Torque and Power
  • Mandrel Bent 16 Gauge Tubing
  • Includes Hangers and Hardware for Easy Installation
  • Every System Tuned on Dynamometer

American Thunder gives you exactly the sound that is promised by the name of the series. The exhaust sound of the American Thunder system has become a symbol of American power that is recognized all over the world. American Thunder is the most popular of the Flowmaster exhaust systems, enhancing power, torque, throttle response and mileage for automobile enthusiasts all over the world.

All Flowmaster exhaust systems give the same improvement of performance. All Flowmaster exhaust systems produce a beautiful deep performance tone. Choosing between the five different exhaust systems is not a technical decision – it is all up to your personal taste. It’s A Sound Decision™. The racing origin is evident in every Flowmaster exhaust system. All the five series of systems are tuned for maximum performance. They differ in technology and tuning, and thus in tone and character, giving you a performance engine sound to your personal liking.

Flowmaster exhaust systems employ two unique technologies, the patented Delta Flow and the Laminar Flow. They give different characters of sound and can be tuned to achieve the desired exhaust note. Flowmaster Exhaust System Technology is so versatile and gives such a high degree of control that it is used both by racers, who want maximum power, and by the U.S. Air Force in Stealth applications, where maximum silence and minimum heat emissions are prime considerations.

Be it for a domestic or import truck, SUV, off-road warrior, daily driver, muscle car, euro-spec cruiser or sport compact vehicle, Flowmaster technicians personally hand select the right muffler, tubing size, resonator, and tip to make the process easy for you. Best of all, Flowmaster stainless steel exhaust systems are covered by a Limited Lifetime Warranty; ensuring that your exhaust will last as long as you own your vehicle. If you choose aluminized steel products, Flowmaster backs them up with a 3-year warranty.

Flowmaster® has its roots in solving the engine noise problems encountered by California racers in the 1980s. In 1983 Flowmaster’s founder, Ray Flugger, created his first patented design of racing silencers, which dampened noise with minimal loss of power. Ray attached handles to ease carrying the square shaped race mufflers through the race pits, and the mufflers became known as the "suitcase mufflers." Today, the innovative Flowmaster mufflers are the result of years of development with top race engine builders, thousands of hours of dyno research and "real-world" on-track testing.

Reviews

(60)
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Flowmaster® - American Thunder™ Exhaust Systems
/5
1-10 of 60 Reviews
Complete exhaust line goes perfectly on my Chevrolet pick-up Very good quality
Posted by Bertrand (St Pierre Brouck) / February 28, 20231993 Chevy CK Pickup
Complete exhaust line goes perfectly on my Chevrolet pick-up Very good quality
Posted by Bertrand (St Pierre Brouck) / February 28, 20231993 Chevy CK Pickup
This went on a 2020 Ram 1500 Bighorn. The instructions were easy to read, and the installation was a breeze. Quality of parts is top notch, and fitment was right in the money. I’m impressed with how well this resonator delete kit woke up my Ram truck. Great sound inside and outside the cabin at low speeds, and it settles down nicely at highway speeds.
Posted by Patrick (Killeen, TX) / April 03, 20222019 Ram 1500
First issue was probably the fault of the carrier, but the system arrived with the box utterly destroyed. Somehow, none of the parts were missing or damaged except for the Flowmaster stickers. Value for the cost seems to be... not great. The hanger rods lack the retaining barb at the end like the stock hangers and instead you're supplied with cheesy push-on retaining washers that will probably rust through the first winter here in the Northeast. The supplied muffler clamps are cheap and flimsy as compared to decent quality ones. The U-bolts are thin and the nuts are only 1/2" hex, not 9/16" and lack the heavy integrated locking washer that the nuts on heavy duty clamps come with. In hindsight, I should have tossed the supplied clamps and bought decent ones to replace them. The biggest issue is that as supplied, the driver's side tailpipe was too short. Assembled using adequate engagement with the muffler outlet, the pipe was touching the differential cover on the rear axle. I had to purchase and insert a 2-1/2" ID X 2-1/2" OD adapter (and some decent clamps) between the muffler outlet and tailpipe in order to space the tailpipe back far enough to prevent the pipe from rubbing through the diff cover and allow the rear axle to be serviced without removing the tailpipe. I expected better fitment from an established company like Flowmaster. On the positive side, the muffler seems to be built very well and the system sounds pretty good. The chrome tips were plated well and look good. The included option of running the exit straight back or out the side was a nice touch. Would I purchase it again, now knowing what I know? Maybe. Would I recommend it to someone without the skill and abilities to correct the deficiencies I found and related above? No.
Posted by Customer / July 21, 20211999 Chevy Silverado 1500
I installed this system on my 2019 Chevy Silverado High Country and it was a welcomed upgrade. The sound is not overpowering at start and idle but when accelerated it provides a throaty sound. I recommend this to all Chevy Silverado owners. You will not be disappointed.
Posted by Jim (Peabody, MA) / June 29, 20212019 Chevy Silverado 1500
Needed to get a new exhaust since the "factory replacement" that a muffler shop put on rusted out in less than 4 years. I've had great success ordering things from CARiD and decided on this Flowmaster system. Install was simple, had to do a little tugging to get the muffler to clear the drive shaft, but that was it. Truck now sounds like a V8 should and I've had a small improvement in mpg as long as I can keep my foot out of it.
Posted by Carl (Toms Brook, VA) / May 29, 20212004 Chevy Silverado 1500
Since installed on my 08 Sierra my engine light is on and has been on for the past month, wish I stayed with stock exhaust.
Posted by Customer / April 29, 20212008 GMC Sierra 1500
Love the look and sound this brings to my 2020 GMC AT4 HD.
Posted by Customer / April 24, 20212020 GMC Sierra 2500
Not my first Flowmaster exhaust system, had one added to another vehicle. This one is just as good as the other one. Easy install, sounds great to my ears when driving my truck. Just the right tone inside the cab with windows up or down.
Posted by Robert (Mesa, AZ) / March 20, 20212018 GMC Sierra 1500
The exhaust fits great but it sounds like a hybrid now. A bit disappointed since it sounds like a pussy now, but at least I'll pass smog.
Posted by Oscar (Auburn, CA) / March 07, 20212003 Chevy Avalanche
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