Walker Exhaust 21409 exhaust muffler for the 2002-2005 Chevrolet Trailblazer 6-cylinder 4.2L and other vehicles lowers exhaust noise before it leaves the vehicle. It is a direct-fit replacement from the Quiet-Flow SS line of Walker Exhaust mufflers.
- Quiet-Flow SS line: 100% stainless steel heads, shell, bushings, louvered tubes and partitions
- Internal drainage system that reduces moisture collection
- Louvered tubes lower noise levels and domed heads help reduce radiated noise
- Internal partitions and mechanically joined tubes allow expansion and contraction as temperatures change, to minimize distortion
- Spun-locked heads and spot welds for stability and longer service life
- Design validated by acoustic and flow testing
Quick facts
- Part: Walker Exhaust 21409 exhaust muffler
- Fits: 2002-2005 Chevrolet Trailblazer 6-cylinder 4.2L and other vehicles
- Material: Stainless steel
- Condition: New
A louder or deeper exhaust note, a rattle from under the car, or rust holes and seam leaks you can see can mean a muffler is worn out. If a failed muffler is the cause, this one replaces it. With the engine off and cool, first look over the muffler, its flange joints and its hangers for holes, cracks or looseness, because a leaking joint can sound much the same.
Fits
The 2002-2005 Chevrolet Trailblazer 6-cylinder 4.2L, the 2002-2005 GMC Envoy 6-cylinder 4.2L and the 2004-2005 Buick Rainier 6-cylinder 4.2L all take this muffler, one per vehicle, and it fits more vehicles besides. If your car is not named here, look up its year and engine in the "Vehicles it fits" section on this page.
Specifications
Fit and size
- Quantity per vehicle: 1
- Inlet: center, 2.5 in outside diameter, 2 bolt welded flange
- Outlet: offset, 2.5 in inside diameter, pipe connection
- Body: 27 in long, 11 in wide, 5.5 in high
- Overall length: 38.42 in
Build and materials
- Type: combination muffler, oval shape
- Material: stainless steel
- Condition: New
- Warranty: Walker limited lifetime warranty
- Country of origin: United States
In the box
One muffler with a hanger.
Installation notes
- Direct-fit, bolt-on replacement; specialized fabrication or welding is not needed.
- Hangers, brackets and pipe routings follow the OE style.
Interchange: 8124799840
Frequently Asked Questions
Will this muffler fit a 2002-2005 Chevrolet Trailblazer 6-cylinder 4.2L?
Yes. Walker Exhaust 21409 is a direct-fit muffler for the 2002-2005 Chevrolet Trailblazer 6-cylinder 4.2L, and the vehicle takes one.
Is there an Envoy muffler here for the 2002-2005 GMC Envoy 6-cylinder 4.2L?
Yes. The 2002-2005 GMC Envoy 6-cylinder 4.2L takes one Walker Exhaust 21409. Other models are covered in the "Vehicles it fits" section.
Are Walker Exhaust mufflers in the Quiet-Flow SS line made of stainless steel?
Yes. This Walker Exhaust 21409 has stainless steel heads, shell, bushings, louvered tubes and partitions, plus an internal drainage system that helps reduce moisture collection.
What are the inlet and outlet sizes on the Walker Exhaust 21409 muffler?
The center inlet is 2.5 in outside diameter with a 2 bolt welded flange. The offset outlet is 2.5 in inside diameter with a pipe connection.
Does this muffler need welding or special fabrication to install?
No. It is a bolt-on, direct-fit replacement with OE-style hangers, brackets and pipe routings, so specialized fabrication or welding is not required.
