Flashark 3.5" Turbo Downpipe for 6.6L L5P Duramax
Upgrade the turbo-outlet section of your 2017–2025 Chevrolet Silverado or GMC Sierra 2500HD/3500HD pickup with the Flashark 3.5-inch turbo downpipe.
Designed specifically for pickup models equipped with the 6.6L V8 L5P Duramax turbo-diesel engine, this downpipe uses larger 3.5-inch tubing and smooth bends to support more efficient exhaust flow through the turbo-outlet section.
Its durable welded construction is designed for the high-temperature environment around the turbocharger. An exhaust heat wrap is included to help manage radiant heat in the engine bay.
Important: This product replaces the turbo downpipe section only. It is not a complete DPF, EGR or DEF delete kit, and those components are not included.
Key Features
- Designed for 2017–2025 6.6L L5P Duramax pickup applications
- 3.5-inch tubing designed to support smoother exhaust flow
- Four-bolt turbo flange with pre-installed studs
- V-band connection at the exhaust-system end
- Durable welded construction
- Heat wrap included for under-hood heat management
- Available in polished silver or black finish
Connection Details
-
Turbo Side: Four-bolt flange with pre-installed studs
-
Exhaust Side: V-band connection
-
Pipe Diameter: 3.5 inches
Compare the flange shape, V-band connection, mounting position and overall pipe routing with your original downpipe before installation.
Package Contents
- 1 × 3.5-inch turbo downpipe in the selected finish
- 1 × exhaust heat wrap
- 2 × stainless-steel heat-wrap retaining clamps/ties
Only the parts shown in the selected variant’s package image are included. Factory hardware may need to be reused unless replacement hardware is specifically shown.
Installation
Professional installation is recommended. Allow the exhaust system to cool completely before removal. Before installation, verify the turbo flange, V-band connection, mounting points and pipe routing.
Installation requirements may vary depending on vehicle condition and any previous exhaust modifications. Do not begin installation if the new downpipe does not match the original connection points.
Performance Expectations
The larger tubing and smooth bends are designed to reduce restriction in the turbo-outlet section and support smoother exhaust flow. Actual changes in sound, throttle response and performance depend on the vehicle condition, calibration and the rest of the exhaust system.
No fixed horsepower, torque or fuel-economy increase is guaranteed.
Shipping, Returns & Warranty
- Orders are normally dispatched within 1–2 business days.
- Unused and uninstalled products may be returned within 30 days in their original packaging, subject to the Flashark return policy.
- Return-shipping coverage applies to confirmed product-quality or fulfillment issues.
- Covered by a 12-month limited warranty against eligible manufacturing defects.
Vehicle Fitment
Confirmed for the following pickup applications equipped with the
6.6L V8 L5P Duramax turbo-diesel engine:
| Year |
Make |
Model |
Engine |
Body Type |
| 2017–2025 |
Chevrolet |
Silverado 2500 HD / 3500 HD |
6.6L V8 L5P Duramax Turbo Diesel |
Pickup |
| 2017–2025 |
GMC |
Sierra 2500 HD / 3500 HD |
6.6L V8 L5P Duramax Turbo Diesel |
Pickup |
Does Not Fit:
- Cab & Chassis trucks
- Chevrolet Silverado or GMC Sierra 1500 models
- Medium-duty 4500HD, 5500HD or 6500HD trucks with the L5D engine
- Gasoline-engine applications
- 2016 or earlier LML, LMM, LBZ, LLY or LB7 Duramax applications
Not sure? Send us your year, make, model, engine code, body configuration and VIN before ordering.
What vehicles does this downpipe fit?
This downpipe fits confirmed 2017–2025 Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD pickup models equipped with the 6.6L V8 L5P Duramax turbo-diesel engine.
Does it fit 2024 and 2025 L5P trucks?
Yes. The confirmed fitment data includes 2024 and 2025 Chevrolet Silverado and GMC Sierra 2500HD/3500HD pickups equipped with the 6.6L L5P Duramax engine. Cab & Chassis applications are excluded.
Does it fit Cab & Chassis trucks?
No. This product is confirmed for pickup models only and does not fit Cab & Chassis configurations.
Does it fit Chevrolet or GMC 4500HD, 5500HD or 6500HD trucks?
No. Medium-duty 4500HD, 5500HD and 6500HD applications commonly use the L5D engine and are not included in the confirmed fitment.
Does it fit a Silverado or Sierra 1500?
No. This downpipe is designed for listed 2500HD and 3500HD pickup applications with the 6.6L L5P Duramax engine. It does not fit 1500-series trucks.
Does it fit earlier LML Duramax trucks?
No. The LML and L5P use different turbo and exhaust configurations. This product does not fit 2016 or earlier LML, LMM, LBZ, LLY or LB7 applications.
Is this a DPF delete pipe?
No. This product replaces the turbo downpipe section only. It is not a complete DPF, EGR or DEF delete kit, and it does not include the parts required to remove those systems.
Does this product require an ECM delete tune?
This product is not supplied with a tuner and should not be presented as requiring an emissions-delete calibration. Tuning requirements depend on the vehicle’s complete exhaust configuration, retained sensors and other modifications. Consult a qualified diesel technician before changing the factory calibration.
What connections does the downpipe use?
The downpipe uses a four-bolt flange at the turbo side and a V-band connection at the exhaust-system side. Compare both connections with the original pipe before installation.
Does it include a sensor bung?
Review the selected variant photos and compare the sensor-port configuration with the original downpipe before installation. Do not assume that a sensor must be transferred unless the replacement pipe has the corresponding port and the installation instructions require it.
What is included in the package?
The standard downpipe package includes one 3.5-inch turbo downpipe, one exhaust heat wrap and two stainless-steel retaining clamps or ties. Only the components shown for the selected variant are included.
Are all installation bolts, gaskets and clamps included?
Only the hardware shown in the package image is included. Some original mounting hardware may need to be reused. Inspect the package and factory hardware before beginning installation.
What is the difference between the silver and black versions?
The versions have different exterior finishes but share the same confirmed vehicle fitment. Select the finish you prefer after confirming your vehicle information.
How much horsepower will this downpipe add?
Results vary depending on vehicle condition, calibration and the rest of the exhaust system. Flashark does not guarantee a fixed horsepower, torque or fuel-economy increase from the downpipe alone.
Is professional installation recommended?
Yes. Access around the turbo outlet can be limited, and factory fasteners may be difficult to remove after repeated heat cycles. Professional installation helps ensure correct flange alignment, sealing and exhaust clearance.
What should I verify before installation?
Compare the replacement part with the original downpipe. Confirm the four-bolt turbo flange, V-band connection, pipe routing, mounting points and any sensor-port locations before removing the original component.
What warranty and return policy applies?
The product includes a 12-month limited warranty against eligible manufacturing defects. Unused and uninstalled products may be returned within 30 days in their original packaging, subject to the published Flashark return and warranty policies.
Easy Return Policy
Every order comes with a 30-day free return, provided the item is brand new, uninstalled, and in its original packaging. We cover return shipping for quality issues. Refunds are processed within 3-5 business days. Click for Return Policy
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