Flowmaster 2.25IN(O)/OUT(O) 40 Series Muffler

Flowmaster's Original 40 Series muffler for the 2011-2013 Ford Mustang V6. Its job is sound: an aggressive tone outside the car and inside the cabin, the original Flowmaster note. If that is the sound you are chasing, this is the muffler Flowmaster built for it.

Why Upgrade to a 40 Series Muffler

Per Flowmaster, here is what the 40 Series brings:

• The original Flowmaster sound. An aggressive tone at the tailpipe and in the driver's seat, so you hear it every time you get on the throttle.
• 16 gauge aluminized steel body. That is the wall thickness and material Flowmaster states for the case.
• Fully MIG welded, which the brand says is for maximum durability, so the seams are welded through rather than left to work loose.
• 2.25 inch inlet and outlet as listed in the title. Measure your existing pipe before you order so you know it matches your system.

Fitment Notes

Our fitment data lists this muffler for the 2011-2013 Ford Mustang with the V6 engine. Does not fit Boss 302, GT, or GT500. The title lists a 2.25IN(O)/OUT(O) size and the (O) marking is not explained in the source copy. [VERIFY: inlet and outlet configuration, confirm the 2.25 inch size and the (O) designation against your exhaust before ordering.]

More Mufflers that fit your Mustang

Install and Honest Talk

This is a muffler swap on the 2011-2013 V6 Mustang, and the source copy does not describe the install: whether it clamps in or welds in, what is in the box, or what has to come off the car to fit it. Read the included instructions before you cut anything on your factory system. What else you need: [VERIFY: supporting parts, clamps or hardware in the box, whether welding is required, tune requirement.]

Honest talk on the sound. Flowmaster calls the tone aggressive outside and inside the car, and inside is the part to think about. A muffler that is louder at the tailpipe is louder in the cabin on a long highway cruise, not just at the on-ramp, and your passengers will notice before you do. Flowmaster gives no horsepower or torque figure in the copy we have, so buy this for the sound, not for a number.

Specs

• Brand: Flowmaster
• Part number: 42443
• Part type: Muffler
• Quantity: [VERIFY: quantity per part number, one muffler or a pair]
• Series: Original 40 Series
• Inlet / outlet: 2.25IN(O)/OUT(O), as listed in the title
• Material: 16 gauge aluminized steel
• Construction: Fully MIG welded

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Free US shipping over $99

Orders over $99 ship free by ground to the lower 48 states. Alaska, Hawaii and Canada are not included; shipping to those addresses is calculated at checkout. Some oversize or heavy parts (long-tube exhausts, bumpers, full lift kits) go freight instead of parcel: free to a commercial address with a loading dock, and residential freight delivery carries an additional charge.

When it ships

Parts ship direct from the distributor warehouse that stocks them, so dispatch timing depends on the part, not on a single cutoff. You get a confirmation with tracking as soon as it leaves, and tracking shows the delivery estimate for your address. If a part is backordered we email you an expected availability date.

Missing or damaged items

Report a short shipment or shipping damage within 5 business days of delivery. For a packing error, send us the date or package code printed on the label along with the part number so we can trace it with the warehouse.

We have a 30-day return policy, which means you have 30 days after receiving your item to request a return.

To be eligible for a return, your item must be in the same condition that you received it, unworn or unused, with tags, and in its original packaging. You’ll also need the receipt or proof of purchase.

To start a return, you can contact us at help@anythingcoyote.com or fill our our contact form. If your return is accepted, we’ll send you a return shipping label, as well as instructions on how and where to send your package. Items sent back to us without first requesting a return will not be accepted. 

You can always contact us for any return question at help@anythingcoyote.com.

Damages and issues
Please inspect your order upon reception and contact us immediately if the item is defective, damaged or if you receive the wrong item, so that we can evaluate the issue and make it right.

Exceptions / non-returnable items
Certain types of items cannot be returned, like perishable goods (such as food, flowers, or plants), custom products (such as special orders or personalized items), and personal care goods (such as beauty products). We also do not accept returns for hazardous materials, flammable liquids, or gases. Please get in touch if you have questions or concerns about your specific item.

Unfortunately, we cannot accept returns on sale items or gift cards.

Exchanges
The fastest way to ensure you get what you want is to return the item you have, and once the return is accepted, make a separate purchase for the new item.

Refunds
We will notify you once we’ve received and inspected your return, and let you know if the refund was approved or not. If approved, you’ll be automatically refunded on your original payment method. Please remember it can take some time for your bank or credit card company to process and post the refund too.