• aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
  • aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD - Stateside Performance - DPF Back - aFe - aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD
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AFE49-44126-B

aFe

aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD

aFe Large Bore-HD DPF-Back Exhaust System - 4 in 409SS w/ Black Tip | 2020-2026 GMC Sierra 3500HD

$808.00 USD
$808.00 USD
Sale Sold out
Shipping calculated at checkout.

The aFe Large Bore-HD 4in DPF-Back Exhaust fits the 2020-2026 GMC Sierra 3500HD 6.6L L5P Duramax and replaces the restrictive factory system with mandrel-bent 409 stainless tubing for stronger flow and a deeper diesel tone.

Install Difficulty: DIY Possible
Bolts to factory hangers and mounting locations with hand tools; typically installs in 60-90 minutes with a vehicle lift, longer on jack stands. Some cutting may be required per the instruction sheet.

Product Overview

This DPF-back system uses 4in mandrel-bent 409 stainless steel tubing with a mitered merge collector to reduce turbulence and boost exhaust velocity. The result is gains in horsepower, torque, and throttle response on the L5P Duramax.

It bolts to factory hangers and mounting locations for a direct-fit install. Finished with dual 5in black 304 stainless intercooled clamp-on tips with a riveted aFe POWER logo plate.

Features & Specifications

  • Fits: 2020-2026 GMC Sierra 3500HD 6.6L L5P Duramax
  • 4in mandrel-bent 409 stainless steel tubing
  • Dual 5in black 304 stainless clamp-on tips
  • Mitered merge collector for higher exhaust velocity
  • 100% MIG-welded construction
  • Bolts to factory hangers and mounting locations
  • Riveted aFe POWER logo plate on tips
  • Some cutting may be required, see instructions

Fitment

This part fits the following vehicles:

Year Make Model Submodel
2020-2026 GMC Sierra 3500 HD AT4
2020-2021 GMC Sierra 3500 HD Base
2020-2026 GMC Sierra 3500 HD Denali
2024-2026 GMC Sierra 3500 HD Denali Ultimate
2022-2026 GMC Sierra 3500 HD Pro
2020-2026 GMC Sierra 3500 HD SLE
2020-2026 GMC Sierra 3500 HD SLT
⚠ Submodel Fitment: If your submodel is not listed in the fitment table above, we cannot confirm fitment. Please contact us before purchasing to verify.

Shipping & Returns

Tracking is typically provided within 3–5 business days; items shipping direct from the manufacturer may take 5–7. Some items are made to order or may be backordered. Questions about stock? Reach us through live chat or email.

Warranty

All warranties are through the manufacturer and are facilitated by Stateside Performance. Some manufacturers require the end user to contact them directly; in that case we will point you to the right contact. Email us with any warranty questions.

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  • Free shipping over $250

    Free shipping applies to items that are shipped via ground through UPS or FedEx and are over $250 going to the continental 48 states. This does not apply to Alaska or Hawaii, and does not apply to any item(s) that are shipped via freight or with any other option other than ground shipping.

    Shipping policy 

  • 30-day returns

    Returns must be requested within 30 days of delivery. Parts must be new, unused, uninstalled, and in original packaging, with an RMA. Some items are final sale.

    Return policy