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Flowmaster American Thunder Dual Exhaust System - Side/Rear Exit (15-18 5.0L)

Market Price $850.99 You Save 13% ($111.02)
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  • Item T527020D
  • MPN# 817725

Will this fit your F-150?

Features, Video & Details

  • Aggressive Flowmaster 40-Series Delta Flow Sound
  • Durable 409 Stainless Steel Construction
  • 3 in. Inlet, Dual 2.5 in. Outlet Mandrel-Bent Tubing
  • 3.5 in. Polished Stainless Steel Tips
  • Simple Bolt-On Installation
  • Choice of Side or Rear Exit
  • Made in the USA
  • Fits 2015-2018 5.0L F-150s, Except for Regular Cabs with a 6.5 ft. Bed

Review & Installation Video

Review & Install Video

What's up everybody? Justin with and this is my review of the Flowmaster American Thunder dual exit catback exhaust system available for five liter Ford F-150s. All right guys, let's get right into things. Now Flowmaster obviously needs no introduction, right? They're one of the largest manufacturers of aftermarket exhaust systems, been around for 50-plus years and they're made right here in the US of A. Now, the American Thunder catback is just one a few different offerings for your new F-150, and it's built around the iconic super 40 series muffler. Now this muffler is the muffler that defined that Flowmaster sound. It's the one they've been using ever since the start, and as you guys just heard, it's gonna give your rig that nice aggressive tone. Now, with that being said, it isn't the most aggressive system they offer. That title goes to the Flowmaster Outlaw series. Still, this is a solid four out of five on my one-to-five or one-to-wake-the-neighbors scale. It is aggressive. It is gonna wake the neighbors a little bit, but they're not going to call the police on you. Now one thing I really do like about this system from Flowmaster is they give you the option of either going with a side rear exit using this pipe or just straight out the back using this pipe, and that's something that a lot of other systems don't really give you the option of, and they do include both pipes here with their kit. One thing that is worth pointing out, though, with the Flowmaster American Thunder catback - this thing has been known to drone a little bit while cruising on the highway. I personally don't think it's that big of a deal. It's almost expected when you're working with that much tone, but it is worth pointing out. Here's my overview - I dunno, maybe turn up the radio a little bit. Price is going to be pretty competitive with some of the other aftermarket catbacks I've seen for the new F-150s. Not going to be the cheapest but it's certainly not gonna be the most expensive either. Therefore, it's gonna land you somewhere in the middle road in regards to overall impact to your wallet. Material-wise, here's what you're looking at guys: full 409-grade stainless steel throughout, 3 inch primary tubing coming off the cat, in to the super 40 series muffler where it kicks down to two-and-a-half inch tubing and then exits out the three-and-a-half inch brightly polished tips featuring that Flowmaster logo. Install, guys, really not that bad. A solid one out of three wrenches on our overall scale of difficulty. Now depending on your bed size or your cab size you might have to cut this system. Flowmaster does include an expansion pipe, but just to give you a for-instance here, we have a supercrew 5-and-a-half foot bed F-150, we did not have to use the expansion pipe and didn't have to cut whatsoever. Either way, really not all that bad. An extra set of hands wouldn't be a bad idea but figure about an hour or two from start to finish getting this thing bolted up. In my opinion, the Flowmaster American Thunder catback would be an awesome choice and here's why. If you can put up with a little occasional drone from time to time, you're going to have a tough sounding system made with full stainless steel and gives you the flexibility of going with a side or rear mounted tip. Be sure to check out American Thunder from Flowmaster for your ride, right here at

Power Packed Performance. AmericanMuscle’s Flowmaster American Thunder Cat-Back Exhaust delivers a sound like no other. It’s a signature roar as complex and power-driven as its architecture. To achieve it is to hear it: a mandrel bent tubing to make better use of your 5.0L F-150's exhaust system, bringing even more unsurpassed on-board control unmistakable in your Coyote-powered F-150’s amplified boom.

Distinctively American-Made. the American Thunder Cat-Back Exhaust is a masterpiece in innovative ingenuity and painstaking engineering. It is focused on delivering peak performance its Flowmaster pedigree expects. The unparalleled Flowmaster 40-Series Delta Flow Sound is more than just upgrade, it’s an entirely new level of power.

Best Of Breed. The proud Flowmaster seal says it all, the top pedigree in construction and materials with a robust 3.0-inch inlet and dual 2.5-inch outlet 16-gauge 409 stainless-steel tubing that can survive even the toughest challenge and environment. The Super 40 Series Delta Flow muffler bridges two 3.5-inch diameter polished stainless-steel tips. You’ve never seen such great looks or heard so much power.

Easy Installation.It’s a worry-free/problem-free process all the way with the American Thunder Cat-Back. Featuring specially-engineered bolt-on set-up, the kit includes all the hardware to make this upgrade replacement for your stock F-150 exhaust seamless. Note, that your cab and bed size might require minor customization of the pipping but no major modifications should be expected.

Application.This Flowmaster American Thunder Cat-Back Exhaust System is designed to fit the 2015 to 2017 5.0L F-150s with the following Cab and Bed sizes.

Fitment: 2015 2016 2017 Details

What's in the Box
  • (1) Inlet Pipe
  • (1) Adapter/Extension Pipe
  • (1) Muffler
  • (1) Right Tailpipe
  • (1) Left Tailpipe - Front
  • (1) Left Tailpipe - Rear
  • (2) Side Exit Pipes
  • (2) Rear Exit Pipes
  • (2) Stainless Tip
  • Hardware Kit
Installation Info
Will it fit my F-150?

People Who Bought This Item Also Bought

Most Helpful Reviews

Not what I thought it was going to be :/

Install wasn't bad except for the horrible clamps. I don't have an impact wrench so I couldn't get them 100 tight so I ended up going to a exhaust shop and having them hit all the clamps with an impact ...

Read More
Helpful (4)

The 5.0 is alive in the F-150

The kit: The kit was package well and all the parts were labeled for easy identification. The only negative would be the lack of instructions. (Missing) This was easy to correct on Flowmaster site. The ...

Read More
Helpful (3)

Overall Rating 4.2 out of 5 stars
Read All 13 Reviews

Customer Photos (1) Submit Your Photo

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4 Questions / 3 Answers

Ask a Question

Can you leave the spare tire in original location after exhaust is installed?


  • The Flowmaster American Thunder Cat-Back Exhaust will allow the spare tire to remain in its stock location, and remain accessible.

    Rob D

Helpful (1)

I'm looking for a cat-back duel tail pipe system (this system) with a Flowmaster 50 series Delta flow muffler. I feel like I have searched everywhere but I can't seem to find what I'm looking for, or it may not be available for my truck, I'm not sure which. I was wondering if you could point me in the right direction. The 40 series is just a little too aggressive for what I wanted, but if the 50 series is not available for this set up I might have to go with the 40. any help would be greatly appreciated. Thank you


  • Unfortunately, we do not carry a Flowmaster catback exhaust that uses the Flowmaster 50 Series muffler. Your best bet would be to contact Flowmaster, or replace the mufflers in a Dual Tail Pipe System with the Flowmaster 50 Series muffler.


Helpful (0)

Those pipes bounce around quite a bit in the video and makes the workmanship look a bit shoddy (not yours, Flowmaster's). Other manufactures seem to secure the pipes to the frame right before the rear bumper and do not bounce around. Do you know if there are hangers or something from Flowmaster that would mitigate that?


This may be a side note but what lift is on the maroon truck. I ordered this muffler and would like my truck to look like this.


  • Hi, The lift kit on our maroon F-150 is a Rough Country 6 in. Suspension Lift Kit Item# T527476. Here is the link

    Chris J

Helpful (0)

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Customer Reviews (13) Write a Review

Overall Rating 4.2

out of 5 stars

Installation Time:Afternoon

Installation Cost:0-$100

  • Loudness / Volume 4.636364 4.6
  • Exhaust Note 4.909091 4.9
  • Fit & Finish 3.818182 3.8
  • Bang For Your Buck 4 4

  • 3/5

    Installation Time: Afternoon

    April 30, 2017

    Not what I thought it was going to be :/

    Install wasn't bad except for the horrible clamps. I don't have an impact wrench so I couldn't get them 100 tight so I ended up going to a exhaust shop and having them hit all the clamps with an impact wrench. I've had the exhaust on for 6 months now and sadly it has started to rust (see pics). For close to $800 I would have expected better quality tubing. I shouldn't have to paint it, but I will. I love the sound, but nothing much else about the whole experience.


    Year: 2016 Submodel: 5.0L V8 XLT

    Helpful (4)

  • 5/5

    Installation Time: Afternoon

    October 16, 2015

    The 5.0 is alive in the F-150

    The kit: The kit was package well and all the parts were labeled for easy identification. The only negative would be the lack of instructions. (Missing) This was easy to correct on Flowmaster site. The instruction could be downloaded. They also have video to watch if you want to view Install: The removal and install is relatively simple. I completed the project on my garage floor with a jack and stands. The only difficulty that I had was lifting the truck at a comfortable/safe work height to remove the factory exhaust. The instruction suggests “cutting” the factory mufflers off which would be easier but also ruins the factory exhaust. It takes some muscle and patients but I did remove it with out cutting it. The installation went smooth. Number 1 Trick/tip. Just “snug each bolt as you install each part of the kit and use a couple bungee cords to help support the kit in place as you install each section. Once you have everything “snugged” in place check to make sure the muffler is level. Once the muffler is level tighten all the bolts starting from the front and working towards the back of the kit. The tips will require some measurements and several adjustments to get each side exactly the same. Performance/sound: The best part! Nothing beats the rumble of the 5.0. The exhaust has a sweet rumble at idle and really becomes powerful when you floor it. The exhaust is not too loud. At highway cruising speed it has a nice tone that does not overpower the cabin. I did not notice an increase in mile per gallon or that dramatic gain in HP.(feels a little quicker in response but I don’t drive my truck that aggressively) My truck sounds great and the dual exhaust out the side looks great. Highly recommend this kit!


    Year: 2015 Submodel: Lariat Lincoln University, PA

    Helpful (3)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    September 02, 2017

    I remember the '70s!

    I'm getting a little lazy to install the exhaust myself, but, I had the new system installed for $100. I haven't had this much fun in a long time. My truck only has 200 miles on it and it sounds like a truck should sound. This exhaust adds personality to the truck that was missing.


    Year: 2017 Submodel: 5.0L V8 XLT

    Helpful (1)

  • 1/5

    Installation Time: Afternoon

    November 05, 2016

    Worst clamps I've ever come across!!!!

    Sounds great lots of drone but that's the way it goes! But every clamp does not hold like it should!!! I used a impact gun and they are all all coming lose! I'm going to weld it solid! This has zero to do with A/M everyone at American muscle is great!!! I have zero complaints with them! But Flowmaster dropped the ball with the fit and finish!


    Year: 2016 Submodel: 5.0L V8 XLT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    October 31, 2016

    Just what the driver ordered!

    Added so much life to my 5.0! Ford should offer this exhaust at the dealerships.


    Year: 2015 Submodel: 5.0L V8 XL

    Helpful (1)

  • 4/5

    September 02, 2016

    Review from Flowmaster American Thunder Cat-Back Exhaust - Split Side/Rear Exit (15-18 2.7L EcoBoost)

    Sounds OK on a V6

    I've heard many exhaust systems on a v6 engine and this is the best sounding one. Its a nice tone, but it does get a bit raspy at higher RPMs, (4k and higher). I've had it on my truck for almost a year now and the sound has stayed consistent. I gave it a 4 out of 5 because the tips are already gathering rust from their first winter.


    Year: 2015 Submodel: 2.7L V6 EcoBoost XL

    Helpful (1)

  • 5/5

    August 02, 2016


    The flowmaster exhaust system was easy to install. Even better with a lift to get under the truck. The sound is amazing. I feel sorry for my neighbors starting in the morning for work


    Year: 2016 Submodel: 5.0L V8 FX4

    Helpful (1)

  • 4/5

    Installation Time: Shop Install

    Installation Cost: 0-$100

    June 30, 2016

    Review from Flowmaster American Thunder Cat-Back Exhaust - Split Side/Rear Exit (15-18 2.7L EcoBoost)

    Flowmaster Exhaust

    Really good product. Looks good on my F150. My only complaint is the drone at certain speeds. Can be a little loud inside the truck. Depending on your preference may be too loud...


    Year: 2015 Submodel: XLT

    Helpful (1)

  • 4/5

    Installation Time: Afternoon

    May 11, 2016

    Review from Flowmaster American Thunder Cat-Back Exhaust - Split Side/Rear Exit (15-18 2.7L EcoBoost)

    Great Product, some minor issues

    First issue is the band clamps for the 2.5 inch side of the exhaust were junk, they did not tighten down enough to secure the pipes in place. Had to do some modifications to get them to kind of work. The tail pipe tips would not stay in place, had to get some clamps from the local auto parts store to get them secure. Next is the highway drone of these around 70MPH, its pretty bad, considering reinstalling the resonator to see if that helps. The quality of the system as whole is great minus the clamps, I do love the option this kit gives you to either side exit or straight out the back. I love the sound below 70MPH so if your just driving around town the sound is awesome, any long highway trips the echoing drone can be a bit much.


    Year: 2016 Submodel: XLT

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    December 02, 2017

    awesome sound, easy install

    This set is all you could hope for. Easy install, great sound and, looks. I like how at idle there is a nice rumble, but just get on the throttle and they wake up. At highway speeds, you can hear the exhaust in the cab, but it's not annoyingly loud, and even at those speeds they wake up when you throttle the gas.


    Year: 2015 Submodel: 5.0L V8 XLT

    Helpful (0)

  • 3/5

    Installation Time: Afternoon

    October 03, 2017

    OK.. but not as I expected..

    First I will have to agree with several other comments I saw about the band clamps -- I found it IMPOSSIBLE to get them tight enough to actually hold the pipes in place.. TWICE within a month I had to get under the truck - re adjust and fully seat all of the pipes again and re - tighten. Finally gave up and had them welded as again after a week started noticing the left tail pipe sagging down lower than the right... Also started noticing corrosion on the pipes almost instantly.. These do sound great, a touch louder than I wanted, yet not loud enough I cant stand them going down the highway.


    Year: 2016 Submodel: 5.0L V8 XLT

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    September 21, 2017

    Music to my ears

    Great sound with my truck. Need two people to install if you don;t have access to a lift and have to jack up. Easy to follow instructions. Well worth the money. Only had one problem. Had to buy U clamps instead of using the ones in the kit. Could not get them tight enough.


    Year: 2015

    Helpful (0)

  • 5/5

    Installation Time: Afternoon

    July 19, 2017


    Couldn't be more happy with this kit. Sounds great, turns heads, easy install, great value.


    Year: 2015

    Helpful (0)

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