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Flowmaster - Force II Cat Back System (817640)

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$649.95

$722.95

You save: $73.00 (10%) off MSRP

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This part fits

  1. 2015 GMC Sierra 2500 HD SLT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  2. 2015 GMC Sierra 2500 HD SLE 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  3. 2015 GMC Sierra 2500 HD Base 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  4. 2015 Chevrolet Silverado 2500 HD WT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  5. 2015 Chevrolet Silverado 2500 HD LTZ 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  6. 2015 Chevrolet Silverado 2500 HD LT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  7. 2013 Chevrolet Silverado 2500 HD 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  8. 2013 GMC Sierra 3500 HD 6.0L V8 cid:364 cc:5967 Crew Cab Pickup 78.8 in. bed
  9. 2013 GMC Sierra 2500 HD WT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  10. 2013 GMC Sierra 2500 HD SLT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  11. 2013 GMC Sierra 2500 HD SLE 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  12. 2013 Chevrolet Silverado 3500 HD 6.0L V8 cid:364 cc:5967 Crew Cab Pickup 78.8 in. bed
  13. 2012 Chevrolet Silverado 3500 HD 6.0L V8 cid:364 cc:5967 Crew Cab Pickup 78.8 in. bed
  14. 2012 GMC Sierra 2500 HD WT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  15. 2012 GMC Sierra 2500 HD SLT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  16. 2012 GMC Sierra 2500 HD SLE 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  17. 2012 GMC Sierra 3500 HD 6.0L V8 cid:364 cc:5967 Crew Cab Pickup 78.8 in. bed
  18. 2012 Chevrolet Silverado 2500 HD 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  19. 2011 Chevrolet Silverado 3500 HD 6.0L V8 cid:364 cc:5967 Crew Cab Pickup 78.8 in. bed
  20. 2011 GMC Sierra 2500 HD WT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  21. 2011 GMC Sierra 2500 HD SLT 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  22. 2011 GMC Sierra 2500 HD SLE 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  23. 2011 Chevrolet Silverado 2500 HD 6.0L V8 cid:364 cc:5967 Extended Cab Pickup 78.8 in. bed
  24. show all...
Authorized Dealer

About this product

Part #: 817640

Flowmaster Force II cat-back exhaust system for the 2011 to 2015 GM 2500HD and 3500HD extended cab and short bed truck is perfect for the person looking for mild to moderate sound levels with all of the performance benefits that you would expect from Flowmaster. This bolt on emissions legal system for the 6.0L V8 gasoline engines features a 50 Series Big Block muffler, mandrel bent 3.50 inch stainless steel tubing, and a polished 4.00 inch stainless steel tip with Flowmaster's logo embossed into it. The exhaust system is covered by Flowmaster's Lifetime Limited Warranty. Designed for an easy fit, this system includes all necessary parts and hardware for installation.

More Details

Exhaust Pipe Bend TypeAssorted
Exhaust Pipe Max Diameter2.500 in.
Exhaust TypeSingle
Exit PositionSingle Side
Exit StyleStraight
Heat Shield AttachedNo
Inlet Diameter3.500 in.
Inlet Inside Diameter3.500 in.
MaterialStainless Steel
Muffler Count1
Muffler Part NumberKit Only
Muffler Series50 Series Big Block
Outlet Diameter3.500 in.
Outlet Outside Diameter4.000 in.
Single or DualSingle
Sound LevelMild/Moderate
System TypeCat Back
Tail Pipe Diameter3.500 in.
Tip Diameter4.000 in.
Tip Length10.000 in.
Tip Quantity1
TitleFlowmaster 817640 Cat-back System 409S - Single Side Exit - Force II - Mild/Moderate Sound
Tubing Diameter3.500 in.
Additional Documents
  1. Certificate of Originpdf
  2. Installation Instructionspdf
  3. Warrantypdf

See what our community says about flowmaster products

Eduardo Ambriz

164

Eduardo Ambriz
2014 Ford Fiesta
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
I chose it because it was a good value in terms of sound for the money. It was also plug and play whereas other systems required a fair bit of modification on my part and I didn't want to deal with that.
Is this your first time buying from this brand? Did you consider other brands?
This is my first time buying from them and I had considered Borla, but went with fFowmaster because of its value.
Was it easy to install? Any installation tips that will help others?
I installed it myself and it wasn't all that easy. The nut is just supposed to be removed from the bolt and the new exhaust should be bolted right back on. The thing is that my bolt was stripped and it was pressed in from the factory so it had to get pushed back out and replaced with a new bolt and nut. Other than that it was plug and play.
Once you've had a chance to use the product, did it meet your expectations?
It is definitely a good value as it gives a deeper tone while making it a bit louder, but not loud enough that it gets annoying. It also doesn't drone too bad when just driving around town.
View on Eduardo's build
Brian Pawlowski

207

Brian Pawlowski
2016 Ford F-150
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Sounds good, good sound for price.I have friends who have flow master.
Is this your first time buying from this brand? Did you consider other brands?
First time for flow master. Was looking at Borla but the price tag was just too much. Borla is more expensive because they use 304 stainless steel where flow master used 409 which is a less durable version of stainless steel, and has been known to rust out.
Was it easy to install? Any installation tips that will help others?
Need a lift or need to cut exhaust out if on ground. Lay out parts first and have clamps ready. Overall wasn't bad at all.
Once you've had a chance to use the product, did it meet your expectations?
Yes! It is loud and sounds good. Time will tell about the rust issues.
View on Brian's build
Kaelen Lillard

132

Kaelen Lillard
1994 Lexus LS 400
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
I wanted the car to have a rumble but not too loud.
Is this your first time buying from this brand? Did you consider other brands?
Yes, I did consider Magnaflow.
View on Kaelen's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
It honestly sounds great
Is this your first time buying from this brand? Did you consider other brands?
No,had a flowmaster on my other truck sounds great
View on Ronnie's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
To make my camaro actually have a little bark.
Is this your first time buying from this brand? Did you consider other brands?
First time
Was it easy to install? Any installation tips that will help others?
Professionally done
Once you've had a chance to use the product, did it meet your expectations?
Yes. Made the car sound amazing.
View on Jarrett's build

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  • California prop 65 warningWARNING: Cancer and Reproductive Harm www.p65warnings.cs.gov

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    About Flowmaster

    Manufacturer of performance exhaust systems, mufflers, cold air intakes, turbo boost modules, catalytic converters, race mufflers, headers and numerous exhaust accessories for late model cars, trucks, off-road, Jeeps, SUV’s, classic muscle cars, powersports vehicles and more. Flowmaster® gives you lots of exhaust choices with 12 designs of chambered mufflers, 3 styles of our exclusive “laminar-flow” mufflers and a new line of FlowFX “straight-through” performance mufflers, along with 5 sound categories of exhaust systems, giving you the customer, the power to custom tailor the sound of your vehicle whether you prefer mild, moderate or aggressive tones and sound levels.

    Benefits of adding this mod

    An upgraded exhaust system is one of the easiest modifications that offers an immediate, noticeable performance improvement. Whether you’re cruising an M3 or modding a diesel truck, an upgraded exhaust will open up the restrictive factory system, allowing your engine to breathe better and deliver peak power! From lighter weight exhaust headers to improved cat-back systems, to better sounding mufflers, modifying your exhaust setup is a great place to express the character of your ride in a unique and cost effective way. Whatever you’re looking for in a modified exhaust system, we can provide the absolute best systems to make your vision a reality.

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    Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.

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    Matt Farah

    Smoking Tire / The Drive

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    Thank you for all the help, really. You guys are awesome. This is all great info and I really appreciate everything you have done to help me with my build.

    James M.

    Ford Focus ST

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    Your customer service is wonderful. Thank you for taking care of this. My review will express all. Thank you!

    Wallace R

    Chevrolet Silverado 1500