Exhaust› Mufflers and Resonators
Flowmaster
40 Series Chambered Muffler 40 Series 2.50 Inch In(C)/Out(O) Aggressive Sound Flowmaster
SKU: F00L 42542
Moderate — 2–4 hours
Description
Part #: 42542
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 is for you.Constructed of 16 gauge aluminized steel and fully MIG welded for maximum durability.No internal packing to blowoutExcellent Street/Strip and Off Road applicationAggressive Sound Exterior Exhaust ToneDurable fully welded 16 gauge aluminized steel
Features:
- 409S Stainless Steel
- No internal packing to blowout
- 3 Year Limited Warranty
- Excellent Street/Strip and Off Road application
- Aggressive And Powerful Exterior Exhaust Tone
- Aggressive Sound Exterior Exhaust Tone
- Notable Interior Resonance
- Durable fully welded 16 gauge aluminized steel
- Excellent Street/Strip And Off Road Application
- No Internal Packing To Blowout
- The Original Two Chamber Design
- Premium Flowmaster Quality
40 Series (TM) Muffler | 2.5 in. Center Inlet/Offset Outlet | Case Dimensions 13 in. Length/4 in. Thick | 19 in. Overall Length | W-9.75 in. | Aluminized Steel
MIA's Description
This muffler has a 2.50-inch center inlet and a 2.50-inch offset outlet. It measures 19 inches in overall length and has a case dimension of 13 inches long by 4 inches thick. The 40 Series is suitable for Street/Strip and Off-Road applications.
Fitment
Fitment Guaranteed
Don’t gamble
on fit.
Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.
Available on iOS & Android
Specifications
| Brand | Flowmaster |
| Part Number | F00L 42542 |
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.
View Full Return Policy