SPDZ1 2017-2025 6.6L Chevy L5P Duramax Diesel 3.5" Downpipe Exhaust
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SPDZ1 2017-2025 6.6L Chevy L5P Duramax Diesel 3.5" Downpipe Exhaust
$199.00
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SPDZ1 3.5" Downpipe Exhaust – 2017–2025 Chevy/GMC 6.6L L5P Duramax
Unleash the true power of your L5P Duramax with the SPDZ1 3.5" Downpipe Exhaust , engineered for maximum flow, durability, and performance. Designed specifically for the 2017–2025 Chevy Silverado & GMC Sierra 2500HD/3500HD 6.6L Duramax (non–Cab & Chassis), this upgrade replaces the restrictive factory downpipe with a free-flowing 3.5” stainless steel system built to handle serious power.
By eliminating the factory DOC and improving exhaust velocity by up to 20% more flow than stock , the SPDZ1 downpipe helps your turbo breathe easier—delivering more horsepower, torque, quicker spool-up, and lower EGTs . Built with high-quality stainless steel , a 4-bolt flange with pre-installed studs , and a precision sealing ring , this downpipe ensures leak-free reliability even under heavy towing or track conditions.
Key Features:
✅ Fitment: 2017–2025 Chevrolet Silverado & GMC Sierra 2500HD / 3500HD (6.6L L5P Duramax, excludes Cab & Chassis models)Performance: 20% better exhaust flow than factory downpipe for more power & efficiencyMaterial: Premium stainless steel, corrosion-resistant and built to lastDesign: 3.5” mandrel-bent tubing with 4-bolt flange & two pre-installed studsReliability: Includes high-quality sealing ring to prevent leaksPower Gains: Faster turbo spool, reduced EGTs, and improved towing performanceInstallation: Direct bolt-on design, quality tested for durability and trouble-free fitment
Built to the SPDZ1 Racing Standard , this downpipe is the perfect balance of power, sound, and reliability —giving your Duramax the aggressive edge it deserves whether on the street, track, or hauling heavy loads.
SPDZ1 Product Warranty Registration
Purchased an SPDZ1 product from Speedzone? Register your SPDZ1 product here
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Domestic orders typically arrive within 3-5 business days . Delivery times are estimated and may vary depending on your location, weather conditions, or other unforeseen factors.
Can I change or return my item?
We hope you love your purchase, but if you need to make a change or return your item, we’ve got you covered! You can initiate a return or exchange within 30 days of receiving your order. Please ensure the product is in its original condition and packaging. For more information on our return policy, please visit our Returns & Exchanges page.
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