Flowmaster vs aFe Cat-Back for 2020-2022 Jeep Gladiator JT

Picking a cat-back exhaust for the 2020-2022 Jeep Gladiator JT 3.6L comes down to two household names that dominate every Gladiator forum thread: Flowmaster and aFe. Both bolt onto the 285-horsepower Pentastar V6 in under 90 minutes, both wake up a truck that leaves the factory far too quiet, and both land in the $450-$646 range that Gladiator owners actually spend. The difference is tone, tubing, and how well the system survives a salty winter. We run both brands in our Tampa shop, so here is the honest breakdown of which Gladiator cat-back is right for your build.

Flowmaster vs aFe: Which Gladiator JT Cat-Back Wins?

For the 2020-2022 Jeep Gladiator JT 3.6L, aFe is the better all-around cat-back and Flowmaster is the better value if you want it loud. aFe's Apollo GT Series uses 2.5-inch mandrel-bent 409 stainless tubing and a high-flow muffler tuned for an aggressive-but-livable tone, while Flowmaster's Outlaw Extreme is built to be the loudest bolt-on in the lineup. Both are cat-back systems, meaning they replace everything from the catalytic converter back — muffler, mid-pipe, and tailpipe — and both are 50-state emissions legal because they leave the factory cats in place.

The Gladiator is the ideal candidate for this upgrade. Jeep ships the JT with a muted single exhaust that hides the Pentastar's naturally aspirated growl, so even a modest cat-back makes a dramatic difference to the driver. Across the five systems we compare below, prices run from about $450 to $646, every option fits the 3.6L V6, and each one is a true bolt-on that needs no tune and throws no check-engine light.

How Much Power Does a Cat-Back Add to the 3.6L Gladiator?

A cat-back exhaust on the 3.6L Gladiator is primarily a sound, weight, and looks upgrade — expect realistic gains of roughly 5 horsepower and 10 lb-ft at the wheels, not a transformation. The Pentastar V6 is naturally aspirated and leaves the factory at 285 hp and 260 lb-ft, and the restriction in that drivetrain lives in the heads and intake, not the muffler. Brands advertise 7-10% gains, but independent dyno testing of bolt-on cat-backs on this engine consistently lands in the single-digit-horsepower range.

That is not a knock — it is why you buy one. Removing the heavy stock muffler trims several pounds, the larger-diameter mandrel-bent tubing sharpens throttle response, and the real payoff is the deep V6 tone the factory system muffles into silence. If your goal is big power, pair the exhaust with an intake and a tune; if your goal is to finally hear your Gladiator, any system below delivers.

The 5 Best Cat-Back Systems for the 2020-2022 Gladiator JT

These are the five cat-back exhausts we recommend for the 2020-2022 Jeep Gladiator JT 3.6L, ranked for how most owners build their trucks. Every system below is in stock, fits the 3.6L V6, and installs as a true bolt-on.

Our top pick. The Apollo GT Series pairs 2.5-inch mandrel-bent 409 stainless tubing with a high-flow muffler and a polished tip for a sound that is noticeably aggressive at throttle but settles down to a civil cruise — no headache-inducing drone on the highway. The 409 stainless construction is the key reason it edges out the field for a daily-driven Gladiator: it shrugs off road salt and moisture far better than aluminized steel. At around $646 it is the priciest option here, but it is the one we would bolt to our own truck.

If you want the loudest, most aggressive Gladiator on the trail, the Outlaw Extreme is Flowmaster's most vocal street system — a wide-open, race-inspired note that announces the truck before you see it. It uses the same 409 stainless tubing as our top pick and is backed by Flowmaster's lifetime limited warranty, yet it undercuts the aFe by nearly $200 at around $450. The trade-off is drone: at steady highway speeds the Outlaw is the one most likely to boom in the cabin. For a weekend trail rig, that is a feature, not a flaw.

The Rock Basher steps up to full 3-inch tubing and a tucked turn-down exit, which is exactly what you want on a lifted, big-tire Gladiator: there is no hanging tailpipe to snag on rocks, and the larger diameter leaves headroom for future intake and tuning mods. It is 409 stainless like the Apollo GT, and at around $500 it slots neatly between the Flowmaster and the premium aFe. Choose this one if your JT sees real trail duty or you plan to add forced induction down the road.

MBRP's dual rear-exit system is for owners who want the twin-tip look out back and a moderate, well-mannered tone. It uses aluminized steel rather than stainless, which is how MBRP keeps the price reasonable while still delivering mandrel-bent 2.5-inch tubing — just know that aluminized will show surface rust sooner than 409 stainless in a salt-belt winter. If you garage the truck or live somewhere dry, it is a lot of exhaust for the money at around $645.

Our budget pick. The FlowFX Extreme is the sensible-daily Flowmaster: a moderate, deep tone with far less drone than the Outlaw, built from the same 409 stainless and carrying the same lifetime warranty, all for about $450. If you love the idea of the Flowmaster name and warranty but have to live with your Gladiator on a long commute, this is the one that will not wear you out at 75 mph.

Gladiator JT Cat-Back Comparison Chart

Here is every system side by side. All five fit the 2020-2022 Gladiator JT 3.6L V6; the two Flowmaster systems also carry fitment through 2025 per the manufacturer.

Which System Is the Loudest — and Which Drones?

The Flowmaster Outlaw Extreme is the loudest cat-back in this group, and the aFe Apollo GT is the best balance of volume and comfort. Flowmaster's Outlaw line is engineered for maximum sound, so it is the clear choice if you want heads to turn — the trade-off is the most cabin drone at highway cruise. The aFe Apollo GT dials in an aggressive note at wide-open throttle but keeps steady-state cruising civil, which is why it is our daily-driver pick.

For the quietest-but-still-sporty setup, the Flowmaster FlowFX Extreme and the MBRP dual system land in the middle: deeper and clearly louder than stock, but easy to live with on a commute. Remember that tip placement and whether you add a tune also shift the Pentastar's tone, so none of these turns a Gladiator into a muscle car — they turn a silent V6 into one you can finally hear.

409 Stainless vs Aluminized: What Survives a Salty Winter?

409 stainless steel resists road-salt and moisture corrosion far better than aluminized steel, which is why it is the smarter choice for any Gladiator that sees winter roads. Four of the five systems here — both aFe units and both Flowmaster units — use 409 stainless. Aluminized steel, used on the MBRP system, has a coated-carbon-steel construction that keeps the price down but will develop surface rust sooner once the coating is chipped or the salt sits on it through a Northern winter.

If you daily your Gladiator through snow and brine, prioritize a 409 stainless system and you will not be chasing rust in three years. If the truck is a fair-weather or garage-kept build, aluminized is a legitimate way to save money without giving up flow or sound.

Installation: Can You Bolt This On at Home?

Yes — every cat-back here is a true bolt-on that a DIYer can install in about 45 to 90 minutes with hand tools and a set of jack stands. Because these are cat-back systems, they connect at the factory flange or slip-joint behind the catalytic converter, use the stock hangers, and require no welding, no cutting, and no tune. There is no check-engine light because the factory catalytic converters and O2 sensors stay in place.

A few shop tips from our Tampa install bay: spray the factory clamps with penetrating oil first, leave every clamp finger-tight until the whole system hangs straight, then torque from front to back so the tips sit even. Keep the tailpipe clear of the spare tire and rear bumper, especially on a lifted JT running the 3-inch Rock Basher.