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Vehicle Info NeededFLOWMASTERPART NUMBER: 389-817940
817940 American Thunder Crossmember-Back Exhaust System 1967-1972 GM K-Series 4WD Trucks V8
$1,04995
Ships on 10/12/2026
Lowest Price GuaranteeGM
Crossmember-Back Exhaust System1967-1972 GM K-Series 4WD Trucks V8 2.500 in. Tubing Dual Rear/Side/Dumped Exit Super 44 Series Mufflers 409S Stainless Steel
Features:
- Aggressive to moderate exterior and interior sound level
- Mandrel-bent tubing with built-in H-pipe crossover pipe
- (3) different tailpipe exhaust exit options for a customized appearance - straight, side exit behind each rear tire, or dumped (turndown) behind the rear tires
- Muffler Dimensions: Body length: 13.500 in., Overall length: 19.500 in.
Notes:
- Exhaust tips are NOT included
- Connector pipes for factory manifolds or headers are NOT included
- Fitment includes long and short bed trucks
Emissions: This part is legal for sale or uses on Emissions-Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing-Use-Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.
The Classic Sound of Flowmaster
Flowmaster American Thunder Exhaust Systems for Truck/SUVs are ideal for the one looking for a moderate-to-aggressive exhaust tone, inside and out. The mufflers are tuned to deliver more power, torque, throttle response, and mileage. With easy fitment in mind, each system has mandrel-bent tubing for maximum performance and flow; and includes all necessary parts and hardware for installation.
Part TypeExhaust System
Product LineFlowmaster American Thunder Exhaust Systems for Truck/SUV
BrandFLOWMASTER
Package Height14.0
Package Width25.0
Package Length49.0
Weight92.75 PG
Tailpipe Diameter (In.)2.5
Muffler Inlet Inside Diameter2.50 in.
Hangers IncludedYes
Main Piping Diameter2.50 in.
Tail Pipe QuantityDual
Inlet TypeWeld-On
Catalytic Converter Quantity0
Exit LocationRear
Muffler Body Length13.25 in.
Sound LevelAggressive / Moderate
Muffler Material409S Stainless Steel
Muffler Body Material409 Stainless Steel
Gasket Or Seal IncludedNo
Pipe ColorSilver
System FinishNatural
Muffler Quantity2
Muffler Inlet Outside Diameter2.63 in.
Exit QuantityDual
Muffler Flanged OutletNo
Catalytic Converter IncludedNo
Heat Shield IncludedNo
Catalytic Converter(S) IncludedNo
Part CategoryPerformance Parts
Hardware IncludedYes
Exhaust Tip Quantity0
Muffler Inlet LocationOffset
Valve IncludedNo
Muffler TypeReflection
Pipe Material409 Stainless Steel
Muffler Body Width9.50 in.
Tail Pipe Tapered OutletNo
Muffler Body ShapeOval
Mounting Bracket IncludedYes
Muffler Outlet Quantity1
Muffler FinishBlack High-Temperature Paint Finish
Mount TypeUses New Hangers (Included)
Clamps IncludedYes
Muffler StyleBaffled
FinishNatural
Exit StyleDual Out Rear
Muffler Body Height4 in.
Tip IncludedNo
Clamping TypeFlat Band
Muffler Flanged InletNo
Mandrel-BentYes
Spring Bolt Kit IncludedNo
Muffler SeriesSuper 44
QuantitySold as a kit.
Muffler IncludedYes
System StyleCrossmember Back
Tail Pipe Outlet Outside Diameter2.50 in.
Muffler ConfigurationCenter/Offset
System Material409S Stainless Steel
Valve TypeNot Applicable
Vendor Part Number817940
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
