Home / Shop / Flowmaster American Thunder Exhaust Systems 17742 System, Thunder, Header-back, Dual, Steel, Aluminized, Split Rear Exit, Chevy, GMC, Kit

Flowmaster American Thunder Exhaust Systems 17742 System, Thunder, Header-back, Dual, Steel, Aluminized, Split Rear Exit, Chevy, GMC, Kit

SKU: FLO17742

Exhaust Systems

Flowmaster

Flowmaster American Thunder Exhaust Systems 17742 System, Thunder, Header-back, Dual, Steel, Aluminized, Split Rear Exit, Chevy, GMC, Kit

SKU: FLO17742

Exhaust Systems

LOW STOCK! Est Ship 4-7 days. HURRY! LOW STOCK. This item is in limited stock at one of our distribution centres. The ETA is the approximate time required to prepare your order for dispatch.

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Description

Flowmaster American Thunder exhaust systems are designed with the latest exhaust technology available--resulting in improved acceleration, passing power, and fuel mileage. A key to these performance upgrades is Flowmaster's use of mandrel-bent tubing, which allows superior exhaust gas flow. The systems also feature mufflers (single or dual) that deliver plenty of the rich Flowmaster sound you expect. Components are built from stainless steel or aluminized steel; and some models include tips. American Thunder exhausts are available in more than a hundred configurations for fitment on specific truck and car applications.

Part Type

A/T Exhaust System 73-87 GM C10 P/U

Data: v4.2 - Upd: 2026-10-16 04:09:18

Specifications

Product Attributes - Brand: Flowmaster
Product Attributes - Manufacturer's Part Number: 17742
Product Attributes - Part Type: Exhaust Systems
Product Attributes - Product Line: Flowmaster American Thunder Exhaust Systems
Product Attributes - UPC: 700042032341
Product Attributes - System Material: Steel
Product Attributes - System Style: Header-back
Product Attributes - Exhaust Type: Dual
Product Attributes - Exit Location: Split rear
Product Attributes - System Finish: Aluminized
Product Attributes - Catalytic Converter(s) Included: No
Product Attributes - Intermediate Pipe Diameter (in.): 2.50 in.
Product Attributes - Muffler Included: Yes
Product Attributes - Muffler Quantity: Two
Product Attributes - Muffler Configuration: Single inlet/Single outlet
Product Attributes - Muffler Style: Chambered
Product Attributes - Muffler Material: 409 stainless steel
Product Attributes - Muffler Finish: Black
Product Attributes - Hardware Included: Yes
Product Attributes - Tailpipe Diameter (in.): 2.50 in.
Product Attributes - Tip Included: No
Product Attributes - Remanufactured: No
Product Attributes - Quantity: Sold as a kit.
Product Attributes - Notes: Not emissions compliant.
Product Attributes - Special Attention: It is illegal to install parts or components that bypass, defeat, or render inoperative the manufacturers’ technology and design necessary to reduce vehicle emissions to meet state and federal Clean Air Act standards.

Reference Information

Brand Name/s	Flowmaster
StreetFX SKU	flo17742
SFX Item ID	4983673
Supplier Item Code	4983673
Manufacturer SKU	17742
Manufacturer UPC	700042032341
Alternative References	FLM17742

Compatibility

Application Data

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1979
Ending Year	1979
Engine Type	L6
Liter	4.8
CID	292
CC	7441
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; LT Swap
Region	United States (USA)
Engine VIN Code	R
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1979
Ending Year	1975
Engine Type	L6
Liter	6.6
CID	400
CC	4097
Engine Size	6.6L/400
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; LT Swap
Region	United States (USA)
Engine VIN Code	R
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1979
Ending Year	1978
Engine Type	V8
Liter	5.0
CID	307
CC	5031
Engine Size	5.0L/307
Engine Family	Chevy diesel
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	L
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1975
Ending Year	1978
Engine Type	V8
Liter	5.0
CID	307
CC	7441
Engine Size	5.0L/307
Engine Family	Chevy diesel
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	D
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1975
Ending Year	1978
Engine Type	V8
Liter	7.4
CID	454
CC	7441
Engine Size	7.4L/454
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	D
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1975
Ending Year	1976
Engine Type	V8
Liter	6.6
CID	400
CC	7439
Engine Size	6.6L/400
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	D
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1979
Ending Year	1976
Engine Type	V8
Liter	5.0
CID	307
CC	7439
Engine Size	5.0L/307
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	S
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1979
Ending Year	1978
Engine Type	V8
Liter	5.0
CID	307
CC	7441
Engine Size	5.0L/307
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; LT Swap
Region	United States (USA)
Engine VIN Code	U
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1987
Ending Year	1978
Engine Type	V8
Liter	6.6
CID	307
CC	7441
Engine Size	5.0L/307
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	G
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1976
Ending Year	1976
Engine Type	V8
Liter	7.4
CID	454
CC	7441
Engine Size	7.4L/454
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD
Region	United States (USA)
Engine VIN Code	S
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1976
Ending Year	1982
Engine Type	L6
Liter	4.1
CID	250
Engine Size	4.1L/250
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Small Block Chevy Swap
Region	United States (USA)
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
Engine VIN Code	S
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1976
Ending Year	1978
Engine Type	L6
Liter	4.1
CID	250
Engine Size	4.1L/250
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	D
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1976
Ending Year	1978
Engine Type	L6
Liter	4.1
CID	250
Engine Size	4.1L/250
Engine Family	Chevy diesel
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System
Region	United States (USA)
Engine VIN Code	D
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	7.4
CID	454
Engine Size	7.4L/454
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; LT Swap
Region	United States (USA)
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
Engine VIN Code	U
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	7.4
CID	305
Engine Size	5.0L/305
Engine Family	Chevy big block Mark IV
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; LS Swap
Region	United States (USA)
Engine VIN Code	U
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	4.8
CID	305
Engine Size	5.0L/305
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; LT Swap
Region	United States (USA)
Engine VIN Code	R
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	4.8
CID	305
Engine Size	5.0L/305
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; LT Swap
Region	United States (USA)
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
Engine VIN Code	R
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	4.8
CID	292
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	R
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	4.8
CID	292
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; LT Swap
Region	United States (USA)
Engine VIN Code	R
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1977
Ending Year	1978
Engine Type	L6
Liter	4.8
CID	292
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Small Block Chevy Swap
Region	United States (USA)
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
Engine VIN Code	R
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1974
Ending Year	1982
Engine Type	L6
Liter	4.8
CID	292
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	V
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1974
Ending Year	1973
Engine Type	L6
Liter	4.8
CID	292
Engine Size	4.8L/292
Engine Family	GM inline 6-cylinder
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; Small Block Chevy Swap
Region	United States (USA)
Engine VIN Code	V
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual
CC	7441

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1985
Ending Year	1973
Engine Type	V6
Liter	4.3
CID	262
CC	7441
Engine Size	4.3L/262
Engine Family	GM V6
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Big Block Chevy Swap
Region	United States (USA)
Engine VIN Code	N
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

Make	GMC
Model	C25
Submodel	SIERRA GRANDE
Beginning Year	1985
Ending Year	1973
Engine Type	V6
Liter	4.3
CID	262
CC	4801
Engine Size	4.3L/262
Engine Family	GM V6
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Hemi Swap Gen III
Region	United States (USA)
Engine VIN Code	N
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Manual

Make	GMC
Model	C25
Submodel	SIERRA CLASSIC
Beginning Year	1985
Ending Year	1973
Engine Type	V6
Liter	4.3
CID	262
CC	7441
Engine Size	4.3L/262
Engine Family	GM V6
Drivetrain	RWD
Application Notes	U/K, U/K; U/K; RWD; Flowmaster American Thunder Crossmember-Back Exhaust System; LS Swap
Region	United States (USA)
Engine VIN Code	N
Body Style	Crew Cab Pickup
Truck Bed Length in. (AAIA)	96.0in, 243.8cm
Transmission	Automatic

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Flowmaster American Thunder Exhaust Systems 17742 System, Thunder, Header-back, Dual, Steel, Aluminized, Split Rear Exit, Chevy, GMC, Kit

Flowmaster American Thunder Exhaust Systems 17742 System, Thunder, Header-back, Dual, Steel, Aluminized, Split Rear Exit, Chevy, GMC, Kit

Description

Part Type

Specifications

Reference Information

Compatibility

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