6.6L Duramax L5P Downpipe-Back Exhaust System | 2017–2026
2017 - 2019
4-inch Downpipe-Back
409 Stainless Steel
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6.6L Duramax L5P Downpipe-Back Exhaust System | 2017–2026
SKU: SKU:ESSS-GM-17-4
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Unlock the full potential of your Chevrolet Silverado or GMC Sierra 2500HD/3500HD 6.6L Duramax L5P with this Downpipe-Back Race Exhaust System. It's built from 16-gauge stainless steel and available for both 2017–2019 and 2020–2026 trucks. Choose a 4-inch or 5-inch system, then choose to run it with or without a muffler. Every version delivers unrestricted flow, sharper throttle response and a deep, aggressive tone built for serious off-road and competition use.
Build the system that fits your truck and your goals by picking one option from each of the three choices below.
Each version is bent to fit its model generation precisely, so be sure to select the year range that matches your truck.
A strong all-round choice for trucks that tow and daily drive. It improves flow and spool over stock while keeping the tone slightly more restrained than the 5-inch system.
Maximum airflow for built trucks and competition use. The larger diameter offers the least restriction and the deepest, most aggressive exhaust note.
A straight-through pipe with nothing in the path. This is the loudest and least restrictive setup, ideal for dedicated race and pull trucks.
Adds a stainless steel muffler to the system for a more controlled tone. A good fit if you want the flow of a race exhaust with less noise on long drives.
Years: 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
Make: GMC, Chevrolet
Model: GMC Sierra 2500HD / 3500HD, Chevy Silverado 2500HD / 3500HD
Engine: 6.6L Duramax V8 Turbo Diesel (L5P)
Configurations: EC, CC, SB, LB and Dually
It's available in two versions: one for 2017–2019 and one for 2020–2026 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks with the 6.6L Duramax L5P. Select the version that matches your truck's model year.
The 4-inch system suits trucks that tow and daily drive, with a slightly more restrained tone. The 5-inch system offers the most airflow and the deepest sound, making it ideal for built trucks and competition use.
The No Muffler option is a straight-through pipe for maximum flow and volume. The With Muffler option adds a stainless steel muffler for a more controlled tone while keeping the race-style flow.
Yes. Off-road race tuning is required for correct performance and to prevent error codes.
Yes. Each kit includes stainless clamps, contour-bent hangers and improved flanges, plus the muffler when that option is selected.
No. This system fits EC, CC, SB, LB and Dually configurations but is not compatible with Cab & Chassis models.
At Tuner Depot, we understand the importance of timely delivery for your performance parts. We're committed to ensuring a seamless shipping experience, striving to dispatch your orders with utmost efficiency and speed.
Our Shipping Policy: Our aim is to dispatch all orders within two business days, providing you with a quick and efficient processing time. However, unforeseen circumstances beyond our control may occasionally impact shipping times.
Factors Affecting Shipping:
We genuinely appreciate your understanding and patience during any unexpected obstacles. Be assured that we will utilize every resource available to deliver your performance parts promptly.
These items can be returned within 30 days of the purchase date, provided they are unopened, unused, and in their original packaging:
The following items are final sale and cannot be returned:
All items we sell include a 90-day manufacturer warranty.
If an item is being returned due to a manufacturer defect, it may be returned for a full refund, exchange, or replacement with a similar item of equal or lesser value.
For eligible items being returned for any other reason, the same options apply: full refund, exchange, or replacement with a similar item of equal or lesser value, provided the item meets the return requirements above.
All returns must be approved by our team before being sent back. We will provide a valid RMA number and prepaid return label for the return.
Please do not send any items back without an approved RMA and the return label provided by us, as returns sent without these will not be accepted or processed.
These products are intended for off-road, race, and competition use only and may not be legal for use on public highways where emissions laws apply. Check your local and state regulations before purchase.
Overall rating: 4.6 / 5 from 193 reviews.
Exhaust was too short, customer service eventually just quit responding after sending picture after picture of it being too short. The exhaust rubs on the transmission hanger bracket so I had to remove and cut that down. I would not buy this kit unless you want to spend extra time modifying it.
6.6L Duramax L5P CAT & DPF Delete Pipe | 2017–2026 GMC/Chevy
It’s more responsive in the pedal.
Fitment wasn’t the greatest could improve a lot
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Tuner depot was very helpful I thought I screwed up on the tune part and flashing the ecm but there customer service told me I didn’t mess it up and helped me through it but one thing for sure is nothing to do with tuner depot but no one every tells you on a first time doing one of these trucks the amount of hours it takes it took me almost 30 hours which if I had the right tools and confidence I could of probably cut it down to about 20 but kit works great it’s got awesome power now and I’ll be doing the down pipe very soon to I highly recommend just buying it and getting it over with because the truck is still very quiet almost like it’s a notch above stock
GM Duramax L5P All-In-One DPF/DEF/EGR Delete Kit (2017-2025)
Just got them installed on my truck yesterday and cannot believe the increase in performance! Can’t wait to take it on a road trip already see more power increase and fuel mileage. Unbelievable would do it again tomorrow!
Love the sound of the straight exhaust especially on the Dirtymax they just sound badass without a muffler
I purchased the efi live sotf tunes along with Dpf delete kit, dpf was good quality, tuner worked with me and not only sent my autocal loaded with a sotf tune but also sent me a few single tunes to use until I installed the switch, the only negative was that 130hp was the max power tune single or switch on the fly, but over all I was pretty happy and service was very good throughout.
As described and shipped quickly.
Worked like a champ
Takes some time but help from support was appreciated
Needs better instructions for install but it was quality parts.
Not sure I like the hanger options but it sounds good and was simple to install.
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Fits well.
Easy to install. Could use a printed copy of the installation procedure.
6.6L Duramax L5P Downpipe 3.5 Inch Turbo Direct Pipe | 2017-2026 GMC Chevrolet
Fit great.
Purchase multiple things from these guys always on time and great quality!
All good, just wished it came with down pipe.
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Easy install and like how it works.
Quality parts.
Delete kit was as it should be, only thing I’d say is the hardware is cheap and should come with bolts that can withstand heat so if a person ever had to remove them they won’t break. Also they don’t volunteer install directions which are super nice to have if you’ve never done one of these. I had to ask several times for the delete, ez lynk, and cam buss plug directions.
The ordering process was easy, the parts came fast and the response from the team has been incredible!
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Love it
still waiting
nice sound without drawing unwanted attention
6 weeks was to long without updates
6.6L Duramax L5P Cold Air Intake | 2017-2026 Sierra/ Silverado
Very easy to work with! Everything fit as it should
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Pretty easy to install, works great
Works s expected
Great product
Timely delivery, great product NOT cheap junk.
L5P Downpipe 3.5 Inch Turbo Direct Pipe | 2017-2026 GMC Chevrolet
Thank you!
Great communication
Sounds great easy installation
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Did not fix on the fling correctly where the downpipe sits and was pushing upwards towards frame
6.6L Duramax L5P CAT & DPF Delete Pipe | 2017–2026 GMC/Chevy
Pretty straight forward install
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Helped quiet down the straight 4" pipe
Should come with clamps
Everything went smooth and lined up great just wish it would’ve came with instructions
6.6L Duramax L5P 5 Inch Downpipe-Back Exhaust System | 2017–2026
Customer service absolutely sucks!!!!
Great product
L5P Downpipe 3.5 Inch Turbo Direct Pipe | 2017-2026 GMC Chevrolet
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