Exterior Components› Body Panels and Components
Flowmaster
FLOWMONSTER 2-CHAMBER MUFFLER ALUMINIZED
SKU: F00L 42543-FM
Moderate — 2–4 hours
Description
This muffler has a 2.50-inch offset inlet and a 2.50-inch offset outlet. Its oval case measures 4 inches high, 9.75 inches wide, and 13 inches long.
Fitment
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Available on iOS & Android
Specifications
| Brand | Flowmaster |
| Part Number | F00L 42543-FM |
Videos
Flowmaster Muffler Chamber Comparison
2 Chamber Flowmaster Original 40 vs. Super 44 Muffler Sound Comparison
How to Spot a Counterfeit Flowmaster Muffler
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The ONLY Flowmaster Video you NEED to watch
Flowmaster Flow FX VS Flowmaster 40 Series Muffler Face-off
2004 Silverado 5.3L Flowmaster Super 44
Flowmaster Muffler Comparison : Muffler Shootout 2
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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