
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 8 - Jul 13
For Your Every Summer RSVP, with Code: SUMMER15
Description
Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve KitThe Allison transmission is the backbone of your L5P Duramax. It's responsible for transmitting large quantities of torque from your V8 diesel powerplant. This torque generates a lot of heat, and if that heat isn't dissipated, it can destroy your transmission. The transmission cooler does a good job of keeping trans fluid temperatures in check, but only if the fluid can reach it. The stock cooling system of the Allison 1000 transmission utilizes an in
The Allison transmission is the backbone of your L5P Duramax. It's responsible for transmitting large quantities of torque from your V8 diesel powerplant. This torque generates a lot of heat, and if that heat isn't dissipated, it can destroy your transmission. The transmission cooler does a good job of keeping trans fluid temperatures in check, but only if the fluid can reach it. The stock cooling system of the Allison 1000 transmission utilizes an in-line thermal bypass valve that controls fluid flow to the transmission cooler. The purpose of this valve is to prevent transmission fluid from flowing to the cooler until it reaches operating temperature. The thermostat inside this valve is prone to failure, however, and when that happens, the fluid never flows to the cooler, and the transmission can overheat. That's why Mishimoto has developed a thermal bypass valve upgrade for your 2017-2019 Chevrolet/GMC 6.6L Duramax. Our CNC-machined aluminum thermal bypass valve not only looks better than the stock unit, but it performs better too. This Mishimoto thermal bypass valve kit includes a fully serviceable thermostat for fast warm-up in cold climates. This kit also includes a thermostat bypass that can be installed to provide constant cooling in warm climates or for use in extreme driving/towing conditions. The Mishimoto thermal bypass valve features strategically machined internal passages, providing improved flow over the stock valve for more effective cooling. In addition, cooling fins machined into the valve body adds even more heat dissipation. This 2017-2019 Chevrolet/GMC 6.6L Duramax L5P Thermal Bypass Valve Kit is built to last a lifetime with a durable black anodized finish and our Mishimoto Lifetime Warranty.This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2017-2019 | Chevrolet | Silverado 2500 HD | High Country |
| 2017-2019 | Chevrolet | Silverado 2500 HD | LT |
| 2017-2019 | Chevrolet | Silverado 2500 HD | LTZ |
| 2017-2019 | Chevrolet | Silverado 2500 HD | WT |
| 2017-2019 | Chevrolet | Silverado 3500 HD | High Country |
| 2017-2019 | Chevrolet | Silverado 3500 HD | LT |
| 2017-2019 | Chevrolet | Silverado 3500 HD | LTZ |
| 2017-2019 | Chevrolet | Silverado 3500 HD | WT |
| 2017-2019 | GMC | Sierra 2500 HD | Base |
| 2017-2019 | GMC | Sierra 2500 HD | Denali |
| 2017-2019 | GMC | Sierra 2500 HD | SLE |
| 2017-2019 | GMC | Sierra 2500 HD | SLT |
| 2017-2019 | GMC | Sierra 3500 HD | Base |
| 2017-2019 | GMC | Sierra 3500 HD | Denali |
| 2017-2019 | GMC | Sierra 3500 HD | SLE |
| 2017-2019 | GMC | Sierra 3500 HD | SLT |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.2 ★★★★★
Based on 1667 reviews
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Product Reviews
★★★★★ 5
Loved
Size: Small, Color: Sliver, Size: Small, Color: Sliver
Loved it. Fit well, sizing was good, however think I could have gotten my son the next size down. We ended up buy a smaller size pants.
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Reviewed in the United States on April 19, 2026
★★★★★ 5
Beat tuxedo ever !!!
Size: Large, Color: Royal Blue
So beautiful. The texture, design, and quality.
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Reviewed in the United States on May 31, 2026
★★★★★ 5
Suit.
Size: Large, Color: Sliver
Great well fitting suit.
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Reviewed in the United States on March 19, 2026
★★★★★ 1
Bad service
Size: XX-Large, Color: Green
Delivered the wrong size returned the suit then they delivered the pants minus the vest and jacket
Not sure went wrong but was definitely not pleased 10 thumbs down 👎🏾
The tux is a very nice tux and color was on point trued it on was very comfortable feels cool enough to we’re in the summer great quality just sent the wrong size I also sent a email never got a response thanks for messing up my plans
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Reviewed in the United States on March 4, 2026
★★★★★ 4
Traje
Size: XX-Large, Color: Dark Black
El traje se lo compré a mi hijo, dude en comprarlo por internet ya que el tiene 16 años es alto y de complexión robusto, el traje viene de tres piezas el bordado del saco es muy bonito la calidad de la tela es muy buena y resistente viene de acuerdo a la talla, no llega ni muy reducido la talla ni muy grande, solo el pantalón viene sin costura para que lo pongas al largo que tú quieres
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Reviewed in the United States on February 5, 2026
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