2017-2025 6.6L GM Duramax L5P 4" Downpipe-Back DPF Delete Pipe DieselPerf

2019-2025 6.7L Dodge Ram Cummins 5'' Downpipe-Back DPF Delete Pipe DieselPerf

2001-2007 6.6L GM Duramax LLY LBZ LB7 4" & 5"Downpipe-back Exhaust DieselPerf

2017-2025 6.6L GM Duramax L5P 4" Downpipe-Back DPF Delete Pipe

$498.00

PATRIOT DAY SALE: 13% OFF

In stock

Ships from USA in 1-2 Business Days

Style

4" Downpipe-Back(2017-2019) 4" Downpipe-Back w/Muffler(2017-2019) 4" Downpipe-Back(2020-2025)

Shipping Policy at Dieselperf, Learn More

Product Specifications

SKU DIPSJ-009S
Vehicle Fitment 2017-2025 L5P 6.6L Duramax

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Please note: All sales of exhaust pipes, straight pipes, and engine pipes are final and Non-Returnable and Non-Refundable

Upgrade your 2017–2025 Chevrolet Silverado or GMC Sierra 2500HD/3500HD equipped with the 6.6L Duramax L5P engine with this 4-inch downpipe-back DPF delete exhaust system.

Constructed from T409 stainless steel, this system uses mandrel-bent 4-inch tubing to provide a consistent exhaust path and a deeper diesel exhaust tone. It connects downstream of the factory turbo downpipe and replaces the exhaust system toward the rear of the truck.

Fits only models equipped with a turbo downpipe featuring an OEM-style 4-bolt flange.

This product does not fit Cab & Chassis trucks, and some shorter wheelbase configurations may require pipe trimming.

CHECK YOUR INLET CONNECTION BEFORE YOU ORDER

Key Features

4-Inch Downpipe-Back Configuration:
Connects downstream of the factory turbo downpipe and replaces the exhaust system toward the rear of the truck.

Year-Specific L5P Fitment:
Separate configurations are available for 2017–2019 and 2020–2025 Chevrolet Silverado and GMC Sierra HD pickups.

Muffler and Non-Muffler Options:
Choose a louder non-muffler configuration or the 2017–2019 muffler-equipped option for more controlled sound.

T409 Stainless Steel Construction:
Designed for durability under high exhaust temperatures and exposure to demanding road conditions.

Mandrel-Bent Tubing:
Smooth bends help maintain a consistent internal pipe diameter through curved exhaust sections.

Heavy-Duty Pipe Walls:
Approximately 2 mm wall thickness provides added strength and structural durability.

Designed for Freer Exhaust Flow:
The 4-inch tubing is designed to reduce restrictive exhaust flow. Actual results vary depending on vehicle condition, configuration, and other modifications.

Available Options

Option	Model Years	Muffler
4" Downpipe-Back	2017–2019	No
4" Downpipe-Back w/Muffler	2017–2019	Yes
4" Downpipe-Back	2020–2025	No

4" Downpipe-Back for 2017–2019

The non-muffler configuration provides a louder and more aggressive exhaust note.

4" Downpipe-Back w/Muffler for 2017–2019

The muffler-equipped configuration helps reduce overall exhaust volume while retaining a deeper 4-inch diesel tone. It may be more suitable for regular driving, towing, and longer highway trips.

4" Downpipe-Back for 2020–2025

Designed for the later L5P truck platform and its corresponding exhaust layout. This option is not listed as including a muffler.

Actual exhaust sound varies based on muffler selection, cab style, bed length, vehicle condition, and other modifications.

Technical Specifications

Specification	Detail
Product Type	Downpipe-back DPF delete exhaust system
Model Years	2017–2025
Vehicle Models	Chevrolet Silverado and GMC Sierra 2500HD/3500HD
Engine	6.6L Duramax V8
Engine Code	L5P
Pipe Diameter	4 inch
Material	T409 stainless steel
Wall Thickness	Approximately 2 mm
Construction	Mandrel-bent tubing
Muffler	Option-dependent
Connection	Factory-style 4-bolt connection required
Cab & Chassis Fitment	Not compatible

Vehicle Fitment

2017–2019 Chevrolet Silverado

Silverado 2500HD with 6.6L Duramax L5P
Silverado 3500HD with 6.6L Duramax L5P

2017–2019 GMC Sierra

Sierra 2500HD with 6.6L Duramax L5P
Sierra 3500HD with 6.6L Duramax L5P

Choose either the muffler or non-muffler 2017–2019 configuration.

2020–2025 Chevrolet Silverado

Silverado 2500HD with 6.6L Duramax L5P
Silverado 3500HD with 6.6L Duramax L5P

2020–2025 GMC Sierra

Sierra 2500HD with 6.6L Duramax L5P
Sierra 3500HD with 6.6L Duramax L5P

Fits only models equipped with a turbo downpipe featuring an OEM-style 4-bolt flange.

Important Fitment Notes

Does not fit Cab & Chassis models.

What’s Included

Depending on the selected configuration, the package includes:

4-inch downpipe-back exhaust pipe sections
Exhaust clamps
Exhaust hangers
Muffler with the option specifically labeled “w/Muffler”

Some factory mounting hardware may need to be reused during installation.

An exhaust tip, sensors, electronic components, flange gasket, bolts, and other unlisted components are not confirmed as included.

Installation Notes

Select the configuration that matches your truck’s model year and physical exhaust connection before removing the factory exhaust system.

For 2020–2025 applications, confirm that the truck has the required factory-style 4-bolt connection.

Minor cutting or trimming may be required for certain short-wheelbase, cab, or bed configurations. Test-fit and align all pipe sections before cutting or fully tightening the clamps.

The available product information does not confirm whether welding is required. Some factory hardware may need to be reused during installation.

Installation time varies depending on vehicle condition, corrosion, cab and bed configuration, available tools, and installer experience. Professional installation is recommended.

After installation, inspect clearance around the frame, suspension, spare tire, fuel lines, brake lines, wiring, and body. Recheck and retighten all exhaust connections after the first complete heat cycle.

Frequently Asked Questions

Is this a short DPF replacement pipe or a complete exhaust system?
This product is a complete 4-inch downpipe-back exhaust system. It includes multiple exhaust sections extending from the factory downpipe connection toward the rear of the truck.

Does this system replace the factory turbo downpipe?
No. It connects downstream of the factory turbo downpipe and is not a turbo-back exhaust system.

What is the difference between the 2017–2019 and 2020–2025 options?
The systems are designed for different truck generations and use year-specific pipe layouts and connections. Select the configuration that matches your truck’s model year.

Which option includes a muffler?
Only the 4" Downpipe-Back w/Muffler (2017–2019) option includes a muffler.

Does the 2020–2025 option include a muffler?
No. The listed 2020–2025 option uses a non-muffler configuration.

Which option is louder?
The non-muffler configurations generally produce a louder and more aggressive exhaust note.

Does the system include an exhaust tip?
An exhaust tip is not listed as included.

Will cutting be required?
Some shorter cab, bed, or wheelbase configurations may require trimming an intermediate pipe. Test-fit the complete system before cutting.

Is welding required?
The available product information does not confirm whether welding is required. Review the physical connections before installation.

Are clamps and hangers included?
Yes. Exhaust clamps and hangers are listed as included. Exact quantities may vary by selected configuration.

Does this system fit Cab & Chassis trucks?
No. This system is not compatible with Cab & Chassis applications.

Will additional vehicle calibration be required?
Replacing factory emissions-related exhaust components may affect vehicle operation and diagnostics. Consult a qualified professional to confirm vehicle compatibility, installation requirements, and applicable legal restrictions.

Compliance Notice

This product alters or replaces factory emissions-related exhaust components. The purchaser and installer are responsible for confirming compliance with all applicable federal, state, and local laws before purchase, installation, or use.

System Specifications & Material

Q1: What’s the difference between 4-inch and 5-inch exhaust systems for diesel trucks?

4-inch Systems: Ideal for stock to moderately tuned engines. This diameter maintains the necessary backpressure to optimize low-end torque, making it the perfect choice for daily driving and consistent towing.
5-inch Systems: Designed for high-horsepower performance builds. These systems maximize exhaust flow to aggressively lower Exhaust Gas Temperatures (EGTs) and unlock peak power for racing or extreme heavy-duty applications.

Q2: Can a magnet stick to this exhaust pipe? Is it genuine stainless steel?

Yes. This pipe is crafted from T-409 Stainless Steel. Unlike 304-grade (non-magnetic), T-409 is a magnetic alloy specifically engineered for automotive exhaust environments. It offers a superior balance of corrosion resistance, high-temperature durability, and cost-effectiveness compared to aluminized steel.

Q3: How thick is the exhaust pipe, and what’s its service life?

The pipe features a heavy-duty 14-gauge (approx. 2mm) wall thickness. Built from durable T-409 stainless, it is engineered to withstand extreme exhaust heat and off-road vibrations for years of rust-resistant, reliable use.

Fitment & Compatibility (LML Duramax)

Q4: Is this a full Turbo-Back system or a Downpipe-Back system?

This is a Downpipe-Back system. It replaces all exhaust components starting after the factory downpipe, including the restrictive DPF and stock piping. To achieve a true "Turbo-Back" setup, an aftermarket performance downpipe is required in addition to this kit.

Q5: I have a 2015 Duramax—how do I ensure I choose the right kit?

The 2015 model year was a "split" year for the LML Duramax. You must verify your truck’s downpipe connection type:Early 2011–2015 Models: The exhaust downpipe attaches via a V-band clamp.Late 2015.5–2016 Models: The exhaust downpipe uses a 3-bolt flange connection.
Please confirm your specific connection design to ensure a perfect bolt-on fit.

Q6: Is this pipe compatible with my LML if I upgrade to a 5-inch exhaust?

Absolutely. This component is engineered to be fully compatible with both 4-inch and 5-inch performance exhaust configurations. It is a top-tier choice for 2015–2016 LML owners looking to maximize exhaust scavenging and overall engine performance.

Performance & Legal Compliance

Q7: Will a DPF delete kit boost my truck’s performance?

Yes. By removing the factory restrictions, you will experience:Lower EGTs: Essential for protecting engine components under load.Faster Spool: Improved turbocharger and throttle response.Better MPG: Increased fuel efficiency (when paired with proper ECU tuning).Reliability: Permanent elimination of DPF clogging and costly "Regen" cycle failures.

Q8: Can I legally drive my truck with a DPF delete on public roads in the US?

Off-Road / Racing Use Only. Removing the Diesel Particulate Filter (DPF) is a violation of U.S. EPA and CARB emissions regulations. Use on public highways may result in significant fines, failed emissions inspections, and legal penalties. Always verify your local and state laws before installation.

Q9: Do I need a tuner after installing this exhaust?

Yes. Modifying the DPF system on a Duramax LML requires a "DPF-off" tune (e.g., EFI Live or EZ Lynk). Without a proper tune, the truck will trigger a Check Engine Light (CEL) and enter "Limp Mode."

Shipping & Delivery Policy

At DieselPerf, we specialize in high-performance diesel emission system accessories. Our mission is simple: to deliver the parts you need with maximum efficiency, security, and transparency. Below are the guidelines we follow to ensure your order reaches you safely.

1. Perfecting Your Delivery

To ensure a seamless experience and avoid unnecessary surcharges, please keep the following in mind:

Precision Matters: Always verify your shipping address at checkout. Accurate data prevents costly rerouting fees.
Address Classification: Carriers determine rates based on zoning. If your business is located in a residential area, it will be classified and billed at the Residential Delivery rate.
Stay Reachable: Please provide a valid phone number. Carriers often need to coordinate delivery windows; missed connections can lead to significant delays.

2. Order Consolidation

To get your parts to you as fast as possible, we ship items as they become available. This means your order may arrive in multiple packages. Rest assured, you will never be charged extra for these split shipments.

3. Our Logistics Network

We partner with world-class carriers, including UPS, FedEx, DHL, USPS, and Amazon Logistics.

Global Fulfillment: We fulfill orders from our strategic hubs in the U.S. and Hong Kong, prioritizing the location closest to you.
Lead Times: While most orders arrive within 5–15 business days, specialty items or factory-direct shipments may require additional transit time.

4. Damaged or Missing Shipments

Your satisfaction is our priority. If your order arrives compromised, please follow this protocol:

For Damaged/Incomplete Deliveries:

Document Immediately: Note any visible damage or missing pieces on the delivery receipt before signing.
Contact Us: Reach out within 2 business days at service@DieselPerf.com or via phone at +1 325-013-1608 / +852 5381 0098.
Preserve Evidence: Keep all original packaging and take clear photos of the damage to expedite your claim.

For Lost Shipments:
If a package goes missing, we will initiate a dock check with the carrier (typically taking 2–7 business days). If the items cannot be located, we will work with you to provide a full replacement or a refund.

5. Estimated Timeframes

Processing: Orders are generally dispatched from our warehouse within 1–2 business days.
Transit: Standard U.S. ground shipping typically takes 7–10 business days, though many items arrive sooner.
Holiday & External Factors: Please account for seasonal peaks (Christmas, Thanksgiving, etc.) and unforeseen "Force Majeure" events like extreme weather, which may naturally extend delivery windows.

Customer Support

Our team is here to help you get back on the road.

Hours: Monday – Friday | 9:00 AM – 6:00 PM
Email: service@DieselPerf.com

All Dieselperf products enjoy a 1-year limited warranty starting from the date of goods receipt, covering defects in product materials and workmanship.

Warranty Coverage

This warranty only covers failures arising from original material and manufacturing defects under proper installation and normal use. The warranty is non-transferable and exclusively available to the original buyer. An order number or valid purchase receipt is mandatory for warranty claims.

Warranty Exclusions

The 1-year limited warranty does not apply to the following circumstances:

Normal wear and tear and surface scratches generated during regular use
Damage caused by improper installation, unauthorized disassembly or modification
Damage resulting from misuse, accidental impact, negligence and natural disasters
Natural aging loss of consumable spare parts
Labor costs incurred from product disassembly, assembly and maintenance

Warranty Claim Process

Submit Application: Email customer service with your order number, detailed fault description and clear photos or videos of product defects.
Claim Review: Our technical team will verify the issue. Additional information or product return inspection may be required.
Settlement Solutions: Upon claim approval, we reserve the right to take one of the following measures:

Repair the defective product
Replace with a brand-new authentic item
Deliver compatible replacement parts for repair

Limitation of Liability

Within the scope permitted by law, Dieselperf shall not be responsible for any special, incidental, indirect or consequential losses, including but not limited to profit losses, business suspension losses and other economic damages.