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Flowmaster 2020-2026 GM Silverado / Sierra 2500HD 6.6L (Crew Cab, Standard Bed) - Outlaw Cat-Back Exhaust System - 818112

MSRP: $1,522.43
$1,049.95
(You save $472.48 )
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SKU:
flo818112
UPC:
090127130162
Box Weight:
67.80 LBS
Shipping:
Calculated at Checkout
Sound Level:
Aggressive
Exhaust Type:
Cat-Back
Series:
Outlaw
Material:
409 Stainless Steel
Pipe Size:
3.50in
Fitment:
2020-2026 GM Silverado / Sierra 2500HD 6.6L (Crew Cab, Standard Bed)
Engine:
6.6L
Warranty:
Lifetime Limited Warranty

Shipping truck Free Shipping On Most Orders Over $99. Within The Continental US. A Signature Will Be REQUIRED For Delivery On All Orders Over $250.00. Exclusions May Apply.  Learn More

This Flowmaster® Outlaw® Cat-back exhaust system for the 2020-2026 Chevy Silverado and GMC Sierra 2500HD/3500HD trucks with the 6.6L gas engine, is perfect if you are looking for an aggressive sound level inside and outside of the truck, with all of the performance benefits that you would expect from Flowmaster®. Maximum increases of up to 9 hp and 9 lb.ft. over the stock exhaust at the rear wheels. Designed for the Crew Cab, Standard Bed (6.5 ft.) models only, this bolt-on, emissions-legal system features a stainless steel Outlaw series muffler and large dual 3.00-inch 409 stainless steel mandrel-bent tailpipes that can be configured to exit either dual straight out the back, or dual out the sides behind the rear wheels which is best suited for towing applications. The system is finished off with polished 4.00-inch stainless steel tips and is covered by our Lifetime Limited Warranty.

Designed for an easy fit, this system includes all necessary parts and hardware for installation.

Highlights

  • 3.50-inch and 3.00-inch mandrel bent 16-gauge 409 stainless steel tubing maximizes exhaust flow and improves durability
  • Super 10 Series performance muffler delivers a deep, aggressive performance tone and improves exhaust flow
  • Includes complete hardware and factory styled hangers in the stock locations for an easy installation
  • Can be configured to exit straight out the rear or out the side depending on preference
  • Max increases of up to 9 hp and 9 lb.ft. over the stock exhaust at the rear wheels
  • Dual 4.00-inch polished stainless steel tips add a custom look
  • Backed by Flowmaster's Lifetime Limited Warranty
  • Outlaw cat-back exhaust system for 6.6L gas V8 applications
  • 3.50-inch inlet to dual 3.00-inch mandrel-bent 409 stainless steel tailpipes
  • Stainless steel Super 10 Series performance muffler
  • Dual rear-exit or dual side-exit configuration
  • Polished 4.00-inch stainless steel exhaust tips
  • Factory-style hangers and complete installation hardware included
  • Designed for Crew Cab, 6.5-foot bed, 159-inch wheelbase models

Product Overview

The Flowmaster Outlaw cat-back exhaust system is designed for 2020-2026 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with the 6.6L gas V8 engine. This emissions-legal bolt-on system delivers an aggressive sound inside and outside the truck while supporting improved exhaust flow.

Built for Crew Cab models with a 6.5-foot bed and 159-inch wheelbase, the system features 3.50-inch and dual 3.00-inch mandrel-bent 409 stainless steel tubing, a stainless steel Outlaw/Super 10 Series performance muffler, and polished 4.00-inch stainless steel tips. The tailpipes can be configured for dual rear exit or dual side exit behind the rear wheels, with the side-exit configuration suited to towing applications. Factory-style hangers, complete hardware, and necessary installation components are included. The system is not compatible with models equipped with a 5th wheel tow hitch.

Flowmaster part number 818112 is designed for an easy installation using the factory hanger locations. The system is covered by Flowmaster's Lifetime Limited Warranty and is reported to provide maximum increases of up to 9 horsepower and 9 lb.-ft. of torque over the stock exhaust at the rear wheels.

Specifications

  • Brand: Flowmaster
  • Part Number: 818112
  • Series: Outlaw
  • Product Type: Cat-Back
  • Vehicle Application: 2020-2026 GM Silverado / Sierra 2500HD 6.6L (Crew Cab, Standard Bed)
  • Pipe Size: 3.50in
  • Material: 409 Stainless Steel
  • Sound Level: Aggressive
  • Warranty: Lifetime Limited Warranty
  • Shipping Weight: 67.8 lbs

Vehicle Fitment

These are suggested fitment applications. Engine, cab, bed, and exhaust configuration vary by vehicle, so contact our team at 1-844-JBO-BOLT and we will confirm fitment for your exact vehicle before you order.

Fitment Notes

  • Fits 2020-2026 GM Silverado/Sierra 2500HD/3500HD 6.6L Gas V8, Outlaw Series, 3.50 to Dual 3.00 Cat-Back, Dual Rear Exit, Stainless Steel Exhaust System Fits Crew Cab with 6.5-foot bed length, 159-inch wheelbase only.
  • Will not fit models with 5th wheel tow hitch installed.

Compatible Vehicles

  • Chevrolet Silverado 2500
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Trims for 2020, 2021, 2022, 2023: HD Custom, HD High Country, HD LT, HD LTZ, HD WT
    • Trims for 2024, 2025, 2026: HD Custom, HD High Country, HD LT, HD LTZ, HD WT, HD ZR2
  • Chevrolet Silverado 2500HD
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Fits: 6.6L Gas V8, Crew Cab, 6.5-foot bed, 159-inch wheelbase
  • Chevrolet Silverado 3500
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Trims: HD High Country, HD LT, HD LTZ, HD WT
  • Chevrolet Silverado 3500HD
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Fits: 6.6L Gas V8, Crew Cab, 6.5-foot bed, 159-inch wheelbase
  • GMC Sierra 2500
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Trims for 2020, 2021: HD AT4, HD Base, HD Denali, HD SLE, HD SLT
    • Trims for 2022: HD AT4, HD Denali, HD SLE, HD SLT
    • Trims for 2023: HD AT4, HD Denali, HD Pro, HD SLE, HD SLT
    • Trims for 2024, 2025, 2026: HD AT4, HD AT4X, HD Denali, HD Pro, HD SLE, HD SLT
  • GMC Sierra 2500HD
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Fits: 6.6L Gas V8, Crew Cab, 6.5-foot bed, 159-inch wheelbase
  • GMC Sierra 3500
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Trims for 2020, 2021: HD AT4, HD Base, HD Denali, HD SLE, HD SLT
    • Trims for 2022: HD AT4, HD Denali, HD SLE, HD SLT
    • Trims for 2023, 2024, 2025, 2026: HD AT4, HD Denali, HD Pro, HD SLE, HD SLT
  • GMC Sierra 3500HD
    • Years: 2020, 2021, 2022, 2023, 2024, 2025, 2026
    • Fits: 6.6L Gas V8, Crew Cab, 6.5-foot bed, 159-inch wheelbase

Frequently Asked Questions

What vehicles does the Flowmaster 818112 fit?
It is listed for 2020-2026 GM Silverado / Sierra 2500HD 6.6L (Crew Cab, Standard Bed). See the Vehicle Fitment section for every listed year, make, and model. Fits 2020-2026 GM Silverado/Sierra 2500HD/3500HD 6.6L Gas V8, Outlaw Series, 3.50 to Dual 3.00 Cat-Back, Dual Rear Exit, Stainless Steel Exhaust System Fits Crew Cab with 6.5-foot bed length, 159-inch wheelbase only. Will not fit models with 5th wheel tow hitch installed.

What will it sound like?
Flowmaster describes this Outlaw cat-back as aggressive.

What is included?
Factory-style hangers, complete hardware, and necessary installation components are included.

What warranty covers it?
The system is covered by Flowmaster's Lifetime Limited Warranty and is reported to provide maximum increases of up to 9 horsepower and 9 lb.-ft.

What is it made of?
Built for Crew Cab models with a 6.5-foot bed and 159-inch wheelbase, the system features 3.50-inch and dual 3.00-inch mandrel-bent 409 stainless steel tubing, a stainless steel Outlaw/Super 10 Series performance muffler, and polished 4.00-inch stainless steel tips.

Who can help me choose the right part?
Call our team at 1-844-JBO-BOLT with your year, make, model, and engine and we will match the right Flowmaster part to your vehicle.

Shipping and Support

This Flowmaster part ships from our warehouse to addresses in the continental USA. For delivery outside the continental USA, see our shipping outside the continental USA page. Questions about application or installation? Call 1-844-JBO-BOLT.

Shipping & Returns

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HOW TO RETURN AN ORDER

To return an order, please contact us HERE, with detailed information regarding the return. We can only accept items that are in new condition and have never been installed. We cannot accept any used, previously installed, or damaged items. If an item is sent back to us used, previously installed and/or damaged, it is now the property of Just Bolt-On Performance Parts and no refund will be issued. All returns must include the provided Return Merchandise Authorization (RMA) form or RGA number, to help expedite the return process. We will then provide the Return Shipping Address for the return. Pictures of the parts being returned are also required. All returns are subject to a 20% Restocking Fee of the original purchase price. Some orders cannot be return – see the list of non-returnable orders below. 

RETURN POLICY

The buyer has 30 days from original purchase to initiate a return RMA and forward tracking information to us. No refund will be given for products that arrive after the 30 days from the original purchase date. Tracking information is required for all returns. When shipping an item back to us, we recommend that you use UPS, FedEx or any other carrier that offers signature confirmation and insurance, as we are not responsible for lost or damaged packages. Only the signature of an Just Bolt-On Performance Parts employee will suffice as proof of delivery. The customer agrees to bear all shipping and insurance charges, and all risk of loss during return shipment. If an order is refused “Returned to Sender”, no refund will be issued. Buyer is responsible for all return shipping charges.

We will not accept a return of an item that is damaged or defective if it has been used/installed, please inspect all orders as soon as you receive them and contact us HERE within 72 hours. If the order is damaged during shipment, Just Bolt-On Performance Parts will replace the item free of charge. 

When you purchase items that qualify for a promotional offer such as Buy "X" number of items, Get "X" number of items free, the discount reflecting the price of the lowest-priced item is proportionally applied to each eligible item. If any item is returned, the refund will be equal to the original price of the item reduced by the proportional discounted amount.

RECEIVED DAMAGED ORDER

We try our best to prevent damage to all packages during transit by packing each order carefully. From time to time, though, damage will occur despite our precautions.  If you receive an item that has been damaged in shipping, please call us within 72 hours of receipt and we will set up a claim for the product. Once this claim has been processed by the courier, we will reach out to you to return the product and send out a replacement.

We may request pictures to further assist with the completion of the claim.

The courier will reach out to you after the claim has been filed over the phone; please provide a reliable contact number when setting up your damage claim.

DEFECTIVE PRODUCTS

If you receive a defective product, please contact us within 72 hours, and we will process your return or replacement free of shipping charge. Contact us HERE to process your return.

In the event of a defect that occurs outside our return policy, but within the manufacturer warranty, please contact the manufacturer directly to process your return. The manufacturer will have sole determination of the outcome of the claim. As a courtesy to our customers, Just Bolt-On Performance Parts will be happy to try to facilitate a thorough review of the claim, but we have no final say in the decision made by the manufacturer (i.e. approvals, denials, fees, etc.).

Just Bolt-On Performance Parts is not responsible for any labor costs which occur as the result of the installation of wrong or defective parts.

NON-RETURNABLE ORDERS

Returns will not be given for the following items:

·       Just Bolt-On Performance Parts gift cards.

·       Any products sold as "Open Box". 

·       Non-defective used or installed items.

·       Wheels that have already been mounted and balance. This includes wheels packages from Just Bolt-On Performance Parts.

·       All special orders, custom, and/or built to order parts. This includes but not limited to, Weld Offroad, Addictive Desert Design, Rigid Industries, Please contact us prior with any questions. 

·       All electronics including but not limited to handheld devices and chargers.

·       Batteries, fluids, lubricants and all maintenance products.

·       All orders that required freight delivery.

·       International orders that shipped outside of the United States.

REFUNDS

Once the return is received, please allow 5-7 business days for the refund to be issued. All items included in the return are fully inspected by our Returns Department prior to issuing a refund. All refunds will be issued to the original payment method. Allow 3-5 business days for the refund to settle back to the original payment method. The original shipping and handling charges are non-refundable. Processing time will vary, depending on your financial institution. 


NEED TO CANCEL

We strongly suggest you call us at 1-844-526-2658 as soon as possible after placing your order if you need to change or cancel it, as orders are processed within minutes!  If you email us, we may not receive them in time to stop the order from shipping out.  Please double-check that your order details are correct before submitting your order during checkout.

An order that has already received tracking information and/or shipped cannot be canceled.  If an order has been assigned a tracking number but the tracking information has not updated, this does not mean the order has not shipped. Please contact us HERE to set up a Return Merchandise Authorization (RMA) once your order has been received.

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Just Bolt-On Performance Parts Frequently Asked Questions