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Vehicle Info NeededFLOWMASTERPART NUMBER: 389-425403
40 Series Original Muffler Dual In/Center Out: 2.500 in./3 in.
$10195
5 left in stock
Ships on Nov 02, 2026
Lowest Price GuaranteeDual In/Center Out
- 40 Series Original Muffler
- Dual In/Center Out: 2.500 in./3 in.
- Aluminized Steel
Muffler fit is universal but may need some adaptation.
The Muffler That Started It All!
Flowmaster's 40 Series Original Mufflers are designed for street/strip and off-road use. These aggressive sounding mufflers deliver a powerful, classic "Flowmaster Sound" from both inside and outside of the vehicle. Give your exhaust system a great muscle car tone with one of these fully MIG welded 40 Series original mufflers.
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Features:
- The original high-performance muffler
- Aggressive sound
- Constructed from stainless steel or 16-gauge aluminized steel
- Fully MIG welded
Part TypeMuffler
Product LineFlowmaster 40 Series Original Mufflers
BrandFLOWMASTER
Package Height4.4
Package Width10.1
Package Length20.1
Weight10.55 PG
Part CategoryExhaust Systems & Components
ShapeOval
Exhaust Tip Quantity0
Outlet Quantity1
Inlet LocationDual
Muffler TypeChambered
Inlet TypeWeld-On
Heat Shield AttachedNo
Body Length13 in.
Inlet Outside Diameter2.63 in.
Inlet Diameter2.50 in.
Clamps IncludedNo
Inlet Quantity2
Sound LevelAggressive
FinishHigh-Temperature Paint
Outlet Outside Diameter3.13 in.
ReversibleNo
Universal Or Specific FitUniversal
Hanger IncludedNo
ColorBlack
Muffler SeriesOriginal 40 Series
TunableNo
Overall Length19 in.
Body Width9.50
Outlet Inside Diameter3 in.
Body MaterialAluminized Steel
Inlet Inside Diameter2.50 in.
Outlet LocationCenter
FitmentUniversal
Body Height4 in.
Outlet TypeSingle
Part FitmentUniversal Fit
Vendor Part Number425403
Package Qty1
Package TypeEA
Items You Need
![Preformed Exhaust Lap Joint Band Clamp for I.D. O.D. Slip Fit Connection [Fits 2 1/2 in. O.D. Pipe]](https://www.jegs.com/images/mini_200/500/555/555-30732.jpg)
JEGS
Preformed Exhaust Lap Joint Band Clamp for I.D. O.D. Slip Fit Connection [Fits 2 1/2 in. O.D. Pipe]
Part Number : 555-30732
$1199$13.99
You Save$2.00
![Preformed Exhaust Lap Joint Band Clamp for I.D. O.D. Slip Fit Connection [Fits 3 in. O.D. Pipe]](https://www.jegs.com/images/mini_200/500/555/555-30733.jpg)
JEGS
Preformed Exhaust Lap Joint Band Clamp for I.D. O.D. Slip Fit Connection [Fits 3 in. O.D. Pipe]
Part Number : 555-30733
$999$10.99
You Save$1.00
JEGS
Part Number : 555-30732
$1199$13.99
You Save$2.00
JEGS
Part Number : 555-30733
$999$10.99
You Save$1.00
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![Rumble Chamber Muffler [3 in./2.5 in. Inlet/Outlet, Center In/Dual Out]](https://www.jegs.com/images/mini_200/600/642/642-r20402.jpg)
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Some parts are not legal for use in California or other states with similar laws / regulations
