Walker 18339 Exhaust Muffler

Brand	Walker 18339
Universal Or Specific Fit	Specific
Shape	Oval
Grade Type	Regular
Inlet Inside Diameter	2.5
Body Width	9.75
Inlet Quantity	1
Outlet Inside Diameter	2.5
Outlet Quantity	1
Reversible	No
Tunable	No
Overall Length	23
Body Height	4.25
Body Length	19
Body Material	Steel
Finish	Aluminized
Inlet 1 Inside Diameter	2.5
Inlet 1 Type	Pipe connection
Inlet Configuration	Offset
Inlet Offset	2.875
Inlet Type	Pipe connection
Muffler Type	Combination
Outlet 1 Inside Diameter	2.5
Outlet 1 Type	Pipe connection
Outlet Configuration	Offset
Outlet Type	Pipe connection
Product line	SoundFX Direct Fit
Fits	Buick, Cadillac, Chevrolet, Oldsmobile, and Pontiac · 31 vehicles

Direct-fit replacement. Installs as a specific-fit exhaust muffler with no modifications needed.

Aluminized steel. Helps resist corrosion for longer service life than low-carbon steel.

Mechanical interior joints. Spun-locked heads add durability and help maintain a quality appearance.

Cross-references AP Exhaust 700087 for the same application. See all 1.

$76.04Free shipping

In stock · usually ships same day before 1pm CST

Step 1 — Confirm fitment

Free return shipping if it doesn't fit when you check fitment here first.

Select your vehicle to confirm fitment

Verify this part fits before purchasing — free returns if it doesn't

Step 2 — Quantity

Free shipping to the continental U.S.

Free returns within 60 days if it doesn't fit when fitment is verified.

Not what you need? See all Exhaust Muffler options

Walker SoundFX Direct Fit Muffler

Walker SoundFX Direct Fit muffler Part Number 18339 is a specific-fit exhaust muffler for select full-size GM and Cadillac applications. It uses an oval steel body with an aluminized finish to support longer service life than low-carbon steel, while maintaining a clean OE-style appearance and controlled exhaust acoustics.

The SoundFX Direct Fit line focuses on direct replacement fitment and consistent sound characteristics for drivers servicing a factory-style exhaust system on vehicles such as the Buick Roadmaster, Chevrolet Caprice, and Cadillac Brougham.

Key Features

Specific-fit exhaust muffler for direct replacement applications
Oval body shape with aluminized steel construction
2.5 in. inlet and 2.5 in. outlet with pipe connection ends
Offset inlet and offset outlet configuration
Combination muffler type for factory-style exhaust service
Mechanical interior joints and spun-locked heads for added durability
Body dimensions: 19 in. length, 9.75 in. width, 4.25 in. height
Overall length: 23 in.

Detailed Description

Walker SoundFX Direct Fit Part Number 18339 is built for direct replacement on select 1985-1993 GM and Cadillac rear-wheel-drive platforms. It is compatible with 1991-1993 Buick Roadmaster, 1985-1993 Chevrolet Caprice, 1990-1992 Cadillac Brougham, 1992 Cadillac Commercial Chassis, 1989-1992 Chevrolet Caprice with Police Package, 1991-1992 Oldsmobile Custom Cruiser, 1985-1986 Pontiac Parisienne with 2.5 in. muffler inlet, and 1985 Chevrolet Impala. This part cross-references AP Exhaust 700087 for the same application.

Built from 100% aluminized steel, this muffler is intended for service replacement where a factory-style fit and controlled exhaust tone are required. The offset inlet and outlet layout, along with the 2.5 in. pipe connections, supports OE-style exhaust routing on the listed vehicles. If the vehicle uses a welded assembly, replace all required parts during service to restore proper exhaust function and alignment.

Common Issues This Muffler Helps Address

Rust-through or corrosion in the original muffler body
Exhaust noise increase from a damaged internal baffle or shell
Restricted exhaust flow caused by a deteriorated muffler
Fitment problems when replacing a factory-style direct-fit muffler
Loss of OE-style exhaust appearance on the rear section

Installation Notes and Tips

Verify inlet and outlet diameter, offset configuration, and overall length before installation. This muffler uses pipe connection ends and is not reversible or tunable. For welded exhaust assemblies, inspect adjoining pipes and replace all required components so the system aligns correctly and seals as intended. Confirm compatibility with the specific vehicle configuration, including police package or 2.5 in. inlet requirements where noted.

Quality Assurance

Walker SoundFX Direct Fit mufflers are engineered with aluminized steel construction, mechanical interior joints, and spun-locked heads to support durability in exhaust service. Part Number 18339 is built to deliver a direct-fit replacement for the listed applications with OE-style appearance and acoustics.

This part fits 31 vehicles

Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

Year	Make	Model	Submodel	Body Type	Drive Type	Liters	Cylinders	Position	Notes
1993	Buick	Roadmaster	—	—	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1993	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1993	Chevrolet	Caprice	—	Wagon	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1993	Chevrolet	Caprice	—	Sedan	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Buick	Roadmaster	—	—	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Cadillac	Brougham	—	—	RWD	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Cadillac	Brougham	—	—	RWD	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Cadillac	Commercial Chassis	Brougham	—	RWD	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Chevrolet	Caprice	—	—	—	5.7L	V8	N/A	with Police Package; If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Chevrolet	Caprice	—	Wagon	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Oldsmobile	Custom Cruiser	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1992	Oldsmobile	Custom Cruiser	—	—	—	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Buick	Roadmaster	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Cadillac	Brougham	—	—	RWD	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Cadillac	Brougham	—	—	RWD	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Chevrolet	Caprice	—	—	—	5.7L	V8	N/A	with Police Package; If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1991	Oldsmobile	Custom Cruiser	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1990	Cadillac	Brougham	—	—	RWD	5.7L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1990	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1990	Chevrolet	Caprice	Base	—	—	5.7L	V8	N/A	with Police Package; If welded assembly, replace all required parts; SoundFX Direct Fit
1989	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1989	Chevrolet	Caprice	Base	—	—	5.7L	V8	N/A	with Police Package; If welded assembly, replace all required parts; SoundFX Direct Fit
1988	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1987	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1986	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1986	Pontiac	Parisienne	—	—	—	5.0L	V8	N/A	with 2.5 (in) Muffler Inlet; If welded assembly, replace all required parts; SoundFX Direct Fit
1985	Chevrolet	Caprice	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1985	Chevrolet	Impala	—	—	—	5.0L	V8	N/A	If welded assembly, replace all required parts; SoundFX Direct Fit
1985	Pontiac	Parisienne	—	—	—	5.0L	V8	N/A	with 2.5 (in) Muffler Inlet; If welded assembly, replace all required parts; SoundFX Direct Fit
No rows match your filter.

Directly replaces or cross-references 1 part number

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.

AP Exhaust — 700087