Flowmaster 21-25 Ford F150 2.7L/3.5L/5.0L American Thunder Cat-Back Exhaust System

Flowmaster's American Thunder cat-back for the 2021-2026 Ford F-150 with the 2.7L, 3.5L or 5.0L engine. It replaces the stock exhaust from the cats back with a Super 40 series muffler, mandrel bent 409 stainless tubing and polished tips, and it makes the truck sound like it means it.

Why Upgrade to the American Thunder Cat-Back

Per Flowmaster, here is what the American Thunder changes:

• A deep, powerful sound out of the Super 40 series muffler. You will hear it every time you get on the throttle, and so will the neighbors.
• Maximum dyno gains of 11 HP and 10 LB.FT at the rear wheels. Modest numbers, but they ride along with the sound.
• Mandrel bent 409 stainless steel tubing with a 3.0-inch inlet pipe and dual 2.5-inch tailpipes, built for maximum exhaust flow and durability.
• Side exit or rear exit: you choose where the dual 3.5-inch polished stainless steel tips show, so the look of the back of the truck is your call.
• All of the necessary hardware is included, it hangs off the factory mounting locations, and it carries Flowmaster's Lifetime Limited Warranty.

Fitment Notes

Fits the 2021-2026 Ford F-150 with the 2.7L, 3.5L or 5.0L engine, in Base and Tremor trims per our fitment data. Does not fit the F-150 Lightning, Raptor or Raptor R. Cab and bed length coverage is not broken out here. [VERIFY: cab and bed configurations covered.]

More Cat-Back that fit your F-150

Install and Honest Talk

The stock exhaust comes off from the catalytic converters back and the American Thunder goes on in its place, using the factory mounting locations, with all of the necessary hardware in the box. Flowmaster calls it an easy installation. The system offers both side exit and rear exit options, so decide which look you want before you crawl under the truck, because it changes how the tailpipes finish.

Honest talk: a Super 40 is a deep, powerful muffler, and deep and powerful in the driveway is deep and powerful inside the cab on the highway too. If you tow long miles or your passengers like a quiet truck, weigh that before you buy. The horsepower and torque figures are the brand's maximum dyno numbers, not a guarantee for every truck. What else you need: [VERIFY: tune requirement, tools and whether a lift is needed, whether the stock exhaust must be cut to come off.] Read the included instructions before you start.

Specs

• Brand: Flowmaster
• Part number: 817979
• Part type: Catback
• Quantity: [VERIFY: sold as a single cat-back system]
• Series: American Thunder
• Engines: 2.7L, 3.5L, 5.0L
• Muffler: Super 40 series
• Tubing: Mandrel bent 409 stainless steel
• Inlet pipe: 3.0-inch
• Tailpipes: Dual 2.5-inch
• Tips: 3.5-inch polished stainless steel
• Exit: Side exit or rear exit options
• Warranty: Flowmaster Lifetime Limited Warranty

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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.