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USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 7 - Jul 12
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 full-flow thermal bypass valve upgrade for your 2017-2019 Chevrolet/GMC 6.6L Duramax. Our CNC-machined aluminum full-flow thermal bypass valve not only looks better than the stock unit, but it performs better too. This Mishimoto thermal bypass valve eliminates the internal thermostat, providing full fluid flow to the transmission cooler in all running conditions. This setup is ideal for owners in warm climates, those performing heavy towing, and trucks needing the best possible cooling efficiency for their transmission. 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 Full-Flow Thermal Bypass Valve Kit is built to last a lifetime with a durable black anodized finish and our Mishimoto Lifetime Warranty.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 1067 reviews
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Product Reviews
★★★★★ 5
Firm and comfortable
Item Package Quantity: 2, Size: Standard
These pillows are well made. Firm, yet comfortable. I am pretty rough with my pillows. I toss and turn frequently. After one year, they are still holding up.
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Reviewed in the United States on May 17, 2026
★★★★★ 4
Quite good. I am actually surprised. Too small for queensize
Item Package Quantity: 2, Size: Queen
These pillows are actually good. After reading a ton of reviews I pulled the trigger on these. I was 100% sure I was going to receive bad quality pillows (too flat or too thick). They do take 24-48 hours to firmen up. Let's see if they flatten out in a few weeks or if they hold up. My wife said the pillow was too thick and it raised her head too much. I don't agree, I sleep perfect on these, no neck pain in the morning.
Update 04/24
These are actually quite small to be considered queen pillows. They have become firm over the last few days.
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Reviewed in the United States on April 20, 2026
★★★★★ 5
Full, Fluffy & Perfectly Supportive Euro Pillows!
Item Package Quantity: 2, Size: European, Item Package Quantity: 2, Size: European
These Euro size pillow inserts are fantastic! They’re soft, full, fluffy, and hold their shape very well. The firmness is perfect — supportive without feeling too hard. They filled my pillow covers beautifully and made the bed look much more luxurious. Great quality for the price and very comfortable for lounging or sleeping. Very happy with this purchase!
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Reviewed in the United States on May 13, 2026
★★★★★ 5
amazing.
Item Package Quantity: 4, Size: Queen
WOW. I was really skeptical, but the other reviews are spot on: these are amazing firm pillows. I really hope they don't lose their firmness and become lumpy like other pillows tend to do. Excellent pillows for the price!!
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Reviewed in the United States on June 7, 2026
★★★★★ 5
Great quality!! Great price
Item Package Quantity: 2, Size: Queen
Bought these for my mom and omg i like them better than the ones I got on Amazon theyre super comfy and they bounce back up they dont flatten and im definitely buying some next for me definitely worth the place great price and the make seems real good quality
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Reviewed in the United States on June 3, 2026