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Exhaust› Mufflers and Resonators
Flowmaster
40 Series Chambered Muffler 40 Series 2.25 Offset In 2.25 Offset Out Aggressive Sound Flowmaster
SKU: F00L 42443
Moderate — 2–4 hours
Overview
This muffler is an excellent choice for street/strip and off-road applications, providing the original Flowmaster sound. It features a noticeable interior resonance along with its aggressive exterior exhaust tone.
Show original supplier description
Part #: 42443
The Original 40 series muffler delivers an aggressive exterior and interior tone. If you're looking for that original Flowmaster sound, this is the muffler for you.Constructed of 16 gauge aluminized steel and fully MIG welded for maximum durability.Durable fully-welded 16 gauge aluminized steelAggressive sound exterior exhaust toneNoticeable interior resonanceExcellent street/strip and off road application
Features:
- Durable Fully Welded 16ga Aluminized Steel
- Durable fully welded 16 gauge aluminized steel
- Aggressive And Powerful Exterior Exhaust Tone
- Aggressive Sound Exterior Exhaust Tone
- Notable Interior Resonance
- Noticeable Interior Resonance
- Excellent Street/Strip And Off Road Application
- Excellent Street/Strip and Off Road application
- No Internal Packing To Blowout
- The Original Two Chamber Design
- Premium Flowmaster Quality
40 Series (TM) Muffler | 2.25 in. Offset Inlet/Outlet | Case Dimensions 4 in. x 9.75 in. x 13 in. | 19 in. Overall Length | Aluminized Steel
Vehicle Symptoms
- Exhaust note too quiet or stock sound
- Exhaust drone at highway speeds
- Rust holes or leaks in current muffler
- Wanting a deeper, more aggressive exhaust tone
- Exhaust system rattling or loose
Relevant Conversations
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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | Flowmaster |
| Part Number | F00L 42443 |
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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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