GM Duramax L5P - Down-pipe Back Race Exhaust System (2017-2025)
Type: Exhaust Systems
Unleash unrestricted power with a full downpipe-back exhaust
Designed for off-road performance, this system removes both the catalytic converter and diesel particulate filter (DPF) on 2017β2025 Duramax 6.6L trucks. Built with stainless steel for durability and performance, itβs a true competition-ready upgrade that transforms exhaust flow and throttle response.
The Black Bandit Downpipe-Back Race Exhaust is a full-performance system engineered for 2017β2025 Chevrolet Silverado and GMC Sierra 2500 & 3500 HD trucks equipped with the L5P 6.6L Duramax. By starting directly at the downpipe and removing all restrictive factory emissions components, this exhaust system boosts horsepower, lowers EGTs, and improves fuel efficiency when paired with custom tuning.
Vehicle Fitment
Compatible Vehicles
- 2017β2025 Chevrolet Silverado 2500HD / 3500HD 6.6L Duramax L5P
- 2017β2025 GMC Sierra 2500HD / 3500HD 6.6L Duramax L5P
Not Compatible With
- Cab & Chassis models
- Any truck without access to tuning software
- On-road vehicles subject to emissions regulations
Product Options
Choose between two system diameters to match your build:
| Pipe Size | Use Case |
|---|---|
| 4-inch | Balanced power, clearance, and install ease |
| 5-inch | Maximum flow and aggressive tone |
A muffler option is also available for quieter performance while maintaining exhaust flow.
Technical Specifications
| Feature | Details |
|---|---|
| Material | Stainless steel tubing |
| Configuration | Downpipe-back design (no DPF, no catalytic converter) |
| Installation | OE-style hangers for secure fitment |
| Tuning Requirement | Yes β Race tuning software is required |
| Muffler Option | Optional β can be added for noise control |
| Bungs | None β for clean, unrestricted flow |
Whatβs Included
- Downpipe-back exhaust system (in 4" or 5")
- OE-style mounting hangers
- Optional muffler (if selected)
- Installation hardware (if applicable)
Key Features
- Starts at the downpipe for full emissions delete capability
- Offers increased horsepower and torque with custom tuning
- Decreases Exhaust Gas Temperatures (EGTs) under heavy load
- Optimized exhaust velocity and backpressure reduction
- Available with or without muffler
- Built from corrosion-resistant stainless steel
- No bungs for smoother, uninterrupted exhaust flow
Benefits
- Better throttle response and low-end torque
- Cooler operating temps during towing or racing
- Increased fuel economy with proper calibration
- More aggressive exhaust tone
- Lightweight construction reduces underbody weight
Important Notes:
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While we ship with all required USMCA/CUSMA paperwork, U.S. Customs or carriers may still apply duties or fees at delivery. For details, see U.S. Customs & Border Protection
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Important Notices
- OffβRoad Use Only
Products sold by JS Speed are intended for offβroad use and may be illegal on public roads where emissions or pollutionβcontrol laws apply. - Check Local Laws
Before purchasing or installing, verify all applicable local, state/provincial, and federal regulations to ensure the modification is legal in your area. - Professional Installation Recommended
These parts should be installed by qualified professional mechanics. Improper installation can cause performance issues or vehicle damage. Unless a product page explicitly states otherwise, installation instructions are not included. Components are designed for users with solid mechanical knowledge, and minor adjustments or modifications may be required for proper fitment. Returns or refunds cannot be accepted due to difficulty completing an installation or the absence of instructions. - Warranty Impact
Use of these parts may void your vehicleβs factory warranty. Confirm with your vehicle manufacturer before purchase and installation. - Limitation of Liability
JS Speed is not responsible for damage, failures, or issues arising from the use or installation of these products. - Product Images
Images are for illustration only and may differ from the actual product due to manufacturer updates or improvements. - No Performance Guarantees
While these products are designed to enhance performance, JS Speed does not guarantee specific performance results.
