DIESELR GM Duramax L5P All In One Kit (2024-2026)
DIESELR GM Duramax L5P All In One Kit (2024-2026) - Cat & DPF Straight - Race Pipe (Stainless Steel) / Level 1 [Stock HP] is backordered and will ship as soon as it is back in stock.
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DIESELR GM Duramax L5P All In One Kit (2024-2026) - Cat & DPF Straight - Race Pipe (Stainless Steel) / Level 1 [Stock HP] is backordered and will ship as soon as it is back in stock.
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Description
Description
The 2024–2026 L5P All-In-One Kit Dieselr is the most complete tuning package available for GM’s latest 6.6L Duramax trucks equipped with the new E42 ECM. Built by techs, tested on real trucks, and packaged for results — this kit gives you everything you need to tune your L5P the right way.
The RTD4 is currently on back order. In-stock items in your order will ship first, while the RTD4 will follow as soon as inventory arrives.
You can still get started right away: follow the post-purchase email to begin the HP Tuners E42 ECM Upgrade service process. This lets you move forward while the RTD4 ships separately.
At the core is the HP Tuners RTD-4 paired with one of Dieselr’s custom Upto +180HP single-level tune files — VIN-matched, dyno-tested, and built for safe torque, better throttle response, and reliable power under load. No inflated claims. No guesswork. Just real results.
To use this kit, your ECM must be unlocked via the HP Tuners GM E42 ECM Upgrade Service. This mail-in service is required to make your factory ECM tune-ready.
About the Required ECM Unlock:
The E42 ECM Upgrade Service is the first step in tuning your 2024–2026 Silverado or Sierra HD. Once your order is placed, you'll receive full shipping instructions to send your original ECM to HP Tuners. After unlock, it’s returned fully licensed and ready for RTD-4 use.
Only the original ECM is accepted — no spares allowed.
Requires 8 HP Tuners credits and VCM Suite (Beta).
Return shipping is included.
At Dieselr, we've already tested this unlock on our own fleet of 2024+ L5Ps — so you're not buying blind. You're buying what we run.
✅ What’s Included in the 2024–2026 L5P All-In-One Kit Dieselr:
- HP Tuners GM Duramax - E42 Global B Unlock & Upgrade Service
- HP Tuners RTD-4
- A Single Dieselr custom tune file [Choose from 5 levels with upto +180HP Gain]
- 8 HP Tuners credits
- 4” or 5” downpipe-back exhaust or the Cat & DPF Straight race pipe
- Dieselr EGR upgrade kit
- Dieselr 3.5" downpipe
Important Notes:
- No SOTF available — single-level tune only
- CAN bus plugs not yet available — Can Bus Systems - NOx & DEF must remain plugged or tied in place. Functionality is unaffected
- 4–5 day pre-sale processing window
Order your 2024–2026 L5P All-In-One Kit Dieselr now — and get tuned by the team building the future of L5P tuning.
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