The Bumper Cutout Guide: How to Pick the Right Exhaust for Your Silverado RST or Trail Boss
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You want to put a loud, aggressive exhaust on your brand-new 2021 Silverado 1500 RST.
You go online and find a great deal on an MBRP Armor Pro side-exit kit. You click buy, it arrives a few days later, and you drag the heavy box under the truck to start the installation.
That's when you look up and realize the massive problem.
The kit you bought features Side Exit Tips designed to dump behind the passenger rear tire.
But your RST has Factory Bumper Cutouts with dual exhaust routing.
If you install this kit, you will literally have two empty, awkward holes in your rear bumper, and a new exhaust pipe hanging low behind your tire where it doesn't belong.
Chevy makes this incredibly confusing for buyers.
- Standard Bumper: (Found on WT, Custom, and some LT trims). Features a flat rear bumper and a single side exit exhaust.
- Integrated Bumper: (Found on RST, LTZ, High Country, and Trail Boss trims). Features a dual rear exit that routes directly through chrome rectangular cutouts in the bumper.
You absolutely must match your aftermarket exhaust system to your specific bumper style.
In this guide, we verify which premium aftermarket kits from brands like Borla and Magnaflow feature the massive "Quad Tips" needed to fill those bumper cutouts perfectly, and which ones are designed for the classic, rugged side-exit look.
Compare Premium Sound Levels
A Mild Daily Growl or Wake-the-Neighbors Aggression?
|
Brand / Series |
Sound Level |
Drone Level |
Best For |
|
Borla Touring |
Mild. |
None. |
Daily Drivers. Slightly louder than stock with a deep, refined tone. Guaranteed zero highway cabin drone. |
|
Magnaflow Street |
Moderate. |
Low. |
Smooth V8 Tone. A classic, deep, smooth rumble that isn't overly raspy or harsh when towing. |
|
MBRP Armor Pro |
Aggressive. |
Medium. |
Raw Sound. A louder, throatier, race-inspired exhaust note for a fantastic price point. |
|
Borla ATAK |
Extreme. |
Low. |
Maximum Volume. The absolute loudest, most aggressive system Borla makes, while still maintaining their acoustic drone-canceling technology. |
Frequently Asked Questions (Exhaust Systems)
Will installing a full Cat-Back exhaust void my Silverado's factory powertrain warranty?
No, you are fully protected by federal law.
In the US, the Magnuson-Moss Warranty Act protects consumers. A dealership cannot void your engine or powertrain warranty simply because you changed the exhaust pipes after the factory catalytic converter.
(Note: If you physically remove or alter the factory catalytic converters—e.g., installing "Long Tube Headers" or "Catless Downpipes"—that is illegal for street use and absolutely will void your powertrain warranty).
What do I do about the terrible sound when the V8 goes into V4 Mode (DFM/AFM)?
You have two distinct options.
When your V8 drops to 4 cylinders on the highway to save a fraction of gas, an aftermarket exhaust can suddenly sound like a broken helicopter or a struggling four-cylinder engine.
- Live with it: Premium exhaust systems (like those from Borla and Magnaflow) utilize tuned acoustic chambers to mask and heavily mute this specific frequency.
- Disable it entirely: Use a premium inline module (like the SCT Performance or Bully Dog tuners) to force the truck's computer to stay in V8 mode 100% of the time. This gives you consistent, aggressive sound and much better throttle response.
My truck has the factory bumper cutouts. Can I change the actual exhaust tips?
Yes, easily.
The factory "tips" you see in the bumper are actually just decorative metal trim rings bolted to the bumper plastic; they are not physically welded to the exhaust pipe.
The Upgrade: If you buy a premium dual-exit system from Borla or MBRP, they often include massive, 5-inch Carbon Fiber or Black Chrome replacement tips that completely fill the factory cutouts for a much more aggressive, finished look.
Make it rumble.
Get the aggressive V8 sound you paid for. Shop our verified collection of premium 2019–2026 Chevy Silverado 1500 Exhaust Systems.