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Flowmaster

Flowmaster 817940 American Thunder Crossmember-Back Exhaust System

Flowmaster 817940 American Thunder Crossmember-Back Exhaust System

Regular price $1,049.95 USD
Regular price Sale price $1,049.95 USD
Mechanic Division pricing available
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Description & Features

Flowmaster 817940 American Thunder Crossmember-Back Exhaust System

This Flowmaster American Thunder dual exhaust system is specifically designed for 1967-1972 Chevrolet and GMC K10, K15/K1500, K20, and K25/K2500 4wd trucks with V8 engines. The system is perfect for the person looking for an aggressive to moderate interior and exterior sound level. Starting at the Crossmember-Back, the exhaust comes complete with a built-in H-pipe crossover for better exhaust scavenging, all mandrel-bent 2.50-inch stainless steel tubing, a pair of Super 44 Series performance mufflers, and your choice of three tailpipe exits (Turndown behind rear tires, side exit behind rear tires, or straight out the back under the bumper). The system includes all hardware necessary for installation and is covered by our Lifetime Limited Warranty. Fits both short and long wheelbase trucks.

  • Crossmember-Back Design Works with Stock Manifolds or Headers, Allowing More Application Options
  • 16-Gauge, 2.50-Inch 409 Stainless Steel Pipes add Durability and Strength
  • Super 44 Mufflers Deliver Increased Performance and an Aggressive to Moderate Sound Level
  • Three Different Tailpipe Exit Options Allow You to Tailor the Look of the Kit to Your Style
  • Mandrel-Bent Pipes Help to Maximize the Exhaust Flow for Better Performance
  • H-Pipe Style Crossover Helps Exhaust Gas Scavenging and Reduces Drone
  • Includes Hangers and Hardware for Installation
  • Lifetime Limited Warranty
Specifications
Brand Flowmaster
California Proposition 65 Yes
California Proposition 65 Chemical Name Chromium (hexavalent compounds)
CARB (California) Compliant Yes
Catalytic Converter Included No
Catalytic Converter Quantity 0
Category Exhaust
Clamping Type Flat Band
Clamps Included Yes
Emission Code 5
Exhaust Series American Thunder
Exhaust Tip Quantity Sold Separately
Exhaust Tip Shape Round
Exit Style Dual Out Rear
Finish Natural
Gasket Or Seal Included No
Grade Type Performance
Hangers Included Yes
Heat Shield Included No
Inlet Type Weld-On
Main Piping Diameter 2.50
Mount Type Uses New Hangers (Included)
Mounting Bracket Included Yes
Muffler (Left) Body Height 4.00
Muffler (Left) Body Length 13.25
Muffler (Left) Body Width 9.50
Muffler (Left) Type Chambered
Muffler (Right) Body Height 4.00
Muffler (Right) Body Length 13.25
Muffler (Right) Body Width 9.50
Muffler (Right) Type Chambered
Muffler Body Height 4.00
Muffler Body Length 13.25
Muffler Body Material 409 Stainless Steel
Muffler Body Shape Oval
Muffler Body Width 9.50
Muffler Color Black
Muffler Finish Black High-Temperature Paint Finish
Muffler Flanged Inlet No
Muffler Flanged Outlet No
Muffler Included Yes
Muffler Inlet Connection Slip-Fit
Muffler Inlet Inside Diameter 2.50
Muffler Inlet Location Offset
Muffler Inlet Outside Diameter 2.63
Muffler Outlet Connection Slip-Fit
Muffler Outlet Diameter 2.50
Muffler Outlet Quantity 1
Muffler Overall Length 19.50
Muffler Part Number Kit Only
Muffler Quantity 2
Muffler Series Super 44
Muffler Type Reflection
part type Exhaust System
Pipe Color Silver
Pipe Material 409 Stainless Steel
Product Type Exhaust System
Sound Level Aggressive / Moderate
Spring Bolt Kit Included No
Sub Category Exhaust and Tail Pipes
Tail Pipe Outlet Outside Diameter 2.50
Tail Pipe Quantity Dual
Tail Pipe Tapered Outlet No
Type Crossmember-back
Valve Included No
Valve Type Not Applicable
Warning California Proposition 65
Packaging Information

Weight: 85.45 lbs
Dimensions: 49 x 25 x 14 IN

Safety

⚠ WARNING: This product can expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information visit www.P65Warnings.ca.gov

Warranty

View Warranty (PDF)

Installation Instructions

View Installation Instructions (PDF)

⚠ Fitment Notes
  • Aggressive to Moderate sound; Super 44 Series Performance Mufflers; 2.50-inch Stainless Steel Pipes.
  • Manifold down pipes and header reducers not included. Fits both long and short bed trucks.

Vehicle Fitment

  • 1967-1972 Chevrolet K10 Pickup Base
  • 1967-1972 Chevrolet K20 Pickup Base
  • 1967-1972 GMC K15/K1500 Pickup Base
  • 1967-1972 GMC K25/K2500 Pickup Base
View full details

California Proposition 65 Warning

This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov ↗.