X-TRA Cool L5P Transmission Cooler Thermostatic Bypass XD396 XDP
Can I pick up my order or have it installed at your shop?
Can I pick up my order or have it installed at your shop?
Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at 636-429-7020 or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.
How do I know if this part fits my vehicle?
How do I know if this part fits my vehicle?
Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.
What if I need to return a product or it’s defective?
What if I need to return a product or it’s defective?
Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)
What's the lead time on custom or fabricated parts?
What's the lead time on custom or fabricated parts?
Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at 636-429-7020 and we’ll confirm current availability or estimated ship dates.
Description
Description
This Part Fits:
| Year | Make | Model | Submodel | Notes |
|---|---|---|---|---|
| 2017 | GMC | Sierra 2500 HD | ||
| 2018 | GMC | Sierra 2500 HD | ||
| 2019 | GMC | Sierra 2500 HD | ||
| 2017 | GMC | Sierra 3500 HD | ||
| 2018 | GMC | Sierra 3500 HD | ||
| 2019 | GMC | Sierra 3500 HD | ||
| 2017 | GMC | Sierra 3500 HD | Denali | |
| 2018 | GMC | Sierra 3500 HD | Denali | |
| 2019 | GMC | Sierra 3500 HD | Denali | |
| 2017 | GMC | Sierra 2500 HD | Denali | |
| 2018 | GMC | Sierra 2500 HD | Denali | |
| 2019 | GMC | Sierra 2500 HD | Denali | |
| 2017 | Chevrolet | Silverado 2500 HD | High Country | |
| 2018 | Chevrolet | Silverado 2500 HD | High Country | |
| 2019 | Chevrolet | Silverado 2500 HD | High Country | |
| 2017 | Chevrolet | Silverado 3500 HD | High Country | |
| 2018 | Chevrolet | Silverado 3500 HD | High Country | |
| 2019 | Chevrolet | Silverado 3500 HD | High Country | |
| 2017 | Chevrolet | Silverado 3500 HD | LT | |
| 2018 | Chevrolet | Silverado 3500 HD | LT | |
| 2019 | Chevrolet | Silverado 3500 HD | LT | |
| 2017 | Chevrolet | Silverado 2500 HD | LT | |
| 2018 | Chevrolet | Silverado 2500 HD | LT | |
| 2019 | Chevrolet | Silverado 2500 HD | LT | |
| 2017 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2018 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2019 | Chevrolet | Silverado 3500 HD | LTZ | |
| 2017 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2018 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2019 | Chevrolet | Silverado 2500 HD | LTZ | |
| 2017 | GMC | Sierra 3500 HD | SLE | |
| 2018 | GMC | Sierra 3500 HD | SLE | |
| 2019 | GMC | Sierra 3500 HD | SLE | |
| 2017 | GMC | Sierra 2500 HD | SLE | |
| 2018 | GMC | Sierra 2500 HD | SLE | |
| 2019 | GMC | Sierra 2500 HD | SLE | |
| 2017 | GMC | Sierra 3500 HD | SLT | |
| 2018 | GMC | Sierra 3500 HD | SLT | |
| 2019 | GMC | Sierra 3500 HD | SLT | |
| 2017 | GMC | Sierra 2500 HD | SLT | |
| 2018 | GMC | Sierra 2500 HD | SLT | |
| 2019 | GMC | Sierra 2500 HD | SLT | |
| 2017 | Chevrolet | Silverado 3500 HD | WT | |
| 2018 | Chevrolet | Silverado 3500 HD | WT | |
| 2019 | Chevrolet | Silverado 3500 HD | WT | |
| 2017 | Chevrolet | Silverado 2500 HD | WT | |
| 2018 | Chevrolet | Silverado 2500 HD | WT | |
| 2019 | Chevrolet | Silverado 2500 HD | WT |
Specifications:
| Country of Origin | USA |
| Sold As | Each |
| Availability | Available |
| Universal | No |
| About |
XDP is a leading retailer, distributor, and manufacturer of top-quality OE, OER, and aftermarket diesel parts and accessories. Strategically positioned across the United States, XDP houses one of the largest and most diverse diesel-specific inventories in the industry. For the last 20 years, XDP has proudly served the diesel community and diesel industry across North America and Canada. We're ready to meet the needs of you and your vehicle, whether it be for work, play, towing or hauling. We know what moves you! |
The XDP X-TRA Cool L5P Transmission Cooler Thermostatic Bypass XD396 helps lower temperatures and prolong the life of the Allison transmission in your 2017-2019 GM 6.6L Duramax L5P. From the factory, the L5P Duramax trucks are equipped with a transmission cooler bypass valve.
The factory installed thermostatic valve is designed to provide quicker warm-ups in cold weather. While this is a great idea in theory, failures in the field are proving that this factory design is unreliable and causes excessive heat in your transmission. The issue with the factory bypass valve is that the design restricts flow, and when the thermostat fails, it causes the fluid to bypass the transmission cooler completely.
This results in elevated temperatures, premature transmission wear, and in some cases can lead to early transmission failure. Once line pressure is increased with common performance upgrades, the issue becomes compounded from the added pressure and heat.
The XDP XD396 Thermostat Bypass is a completely re-designed bypass block made from 6061 billet aluminum. This bypass valve removes the factory thermostat and allows for unrestricted flow to the transmission cooler at all times. This unrestricted flow can provide up to a 50 degree drop in transmission fluid temperature!
This results in better cooling, less wear and tear, and in many cases can help extend transmission life. This valve also allows for a transmission fluid flush without requiring a hot flush machine as there is no thermostat required to open.
Features:
- Direct-Fit
- Replacement No Cutting Of Factory Lines
- Easily Installs With Hand Tools
- Helps Improves Transmission Life
- Eliminates Hot Fluid Recirculation
- Lowers Transmission Fluid Temperature Up To 50 Degrees
