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    • Mishimoto 12-18 Jeep Wrangler JK Transmission Thermal Bypass Valve Kit
    • Mishimoto 12-18 Jeep Wrangler JK Transmission Thermal Bypass Valve Kit
    • Mishimoto 12-18 Jeep Wrangler JK Transmission Thermal Bypass Valve Kit
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    Mishimoto 12-18 Jeep Wrangler JK Transmission Thermal Bypass Valve Kit

    Vendor: Mishimoto
    SKU: MISMMTC-JK-TBV
    Save $15.05
    Sale Price $148.95 Regular Price $164.00
    Fast Fulfillment: In-stock parts typically ship same day or next business day.
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    The transmission in your 2012-2018 Jeep Wrangler JK is the heart of its drivetrain. Whether you're hauling groceries or hitting the trail, it's vital to keep it performing at its best, and keeping the transmission fluid cool is crucial to that goal.In an attempt to balance driveability and the health of your transmission, Jeep fitted a thermostatic bypass valve to the lines that feed the transmission cooler. This valve ensures fluid doesn't flow through the cooler before the transmission reaches operating temperature, preventing overcooling in cold environments. However, when the thermostat in this valve fails, it's almost a guarantee your transmission will overheat. Moreover, those who live in hot climates will likely never have to worry about overcooling, rendering the valve a useless flow restriction.That's why Mishimoto has developed a performance thermostatic bypass valve for the 2012-2018 Jeep Wrangler JK. Our performance thermostatic bypass valve features a fully-serviceable and removable thermostat. For those who live in hot climates, the thermostat can be replaced with the included bypass to allow full flow to the transmission cooler at all times. Speaking of flow, the Mishimoto performance thermostatic bypass provides increased flow over the stock valve to ensure your transmission cooler operates at peak efficiency, even with the thermostat installed. The included thermostat opens at the stock temperature of 160F (71C), but the valve can be customized to suit your needs with any available Mishimoto thermostat.The Mishimoto performance thermostatic bypass valve is a direct-fit and is made from durable aircraft-grade aluminum that's anodized to withstand even the harshest environments. Like all of our Jeep products, our performance thermostatic bypass valve is backed by our Mishimoto Lifetime Warranty.

    • Durable CNC-machined billet aluminum design
    • Direct-fit for 2012-2018 Jeep Wrangler JK
    • Installs in less than 1 hour

    This Part Fits:

    Year Make Model Submodel
    2005-2007,2011-2014 Chrysler 300 Base
    2005-2014 Chrysler 300 C
    2012-2014 Chrysler 300 C Luxury
    2005-2010 Chrysler 300 C SRT8
    2005-2012 Chrysler 300 Limited
    2008-2009 Chrysler 300 LX
    2010,2012-2014 Chrysler 300 S
    2009 Chrysler 300 Signature Series
    2012-2014 Chrysler 300 SRT8
    2013 Chrysler 300 SRT8 Core
    2005-2010 Chrysler 300 Touring
    2009-2014 Dodge Challenger R/T
    2012 Dodge Challenger R/T Classic
    2014 Dodge Challenger Rallye Redline
    2009-2011 Dodge Challenger SE
    2008-2014 Dodge Challenger SRT8
    2012-2014 Dodge Challenger SXT
    2012 Dodge Challenger SXT Plus
    2006-2007 Dodge Charger Base
    2017-2018 Dodge Charger Daytona
    2017-2018 Dodge Charger Daytona 392
    2006 Dodge Charger Daytona R/T
    2018-2019 Dodge Charger GT
    2018 Dodge Charger GT Plus
    2006-2019 Dodge Charger Pursuit
    2006-2019 Dodge Charger R/T
    2017-2018 Dodge Charger R/T 392
    2015-2016 Dodge Charger R/T Road & Track
    2015-2018 Dodge Charger R/T Scat Pack
    2019 Dodge Charger Scat Pack
    2006-2017 Dodge Charger SE
    2015-2018 Dodge Charger SRT 392
    2015-2019 Dodge Charger SRT Hellcat
    2006-2010,2012-2014 Dodge Charger SRT8
    2006-2010,2012-2019 Dodge Charger SXT
    2012,2018 Dodge Charger SXT Plus
    2018 Dodge Charger SXT Plus Leather
    2011-2013 Dodge Durango Citadel
    2011-2013 Dodge Durango Crew
    2011 Dodge Durango Express
    2011 Dodge Durango Heat
    2011-2013 Dodge Durango R/T
    2012-2013 Dodge Durango Special Service
    2012-2013 Dodge Durango SXT
    2005-2008 Dodge Magnum R/T
    2005-2008 Dodge Magnum SE
    2006-2008 Dodge Magnum SRT8
    2005-2008 Dodge Magnum SXT
    2005 Dodge Magnum SXT Special Edition
    2010-2011 Dodge Nitro Detonator
    2010-2011 Dodge Nitro Heat
    2007-2009 Dodge Nitro R/T
    2009-2011 Dodge Nitro SE
    2010-2011 Dodge Nitro Shock
    2007-2009 Dodge Nitro SLT
    2007-2008,2010-2011 Dodge Nitro SXT
    2009-2010 Jeep Commander Limited
    2009 Jeep Commander Overland
    2009-2010 Jeep Commander Sport
    2007-2013 Jeep Grand Cherokee Laredo
    2007-2013 Jeep Grand Cherokee Limited
    2007-2009,2011-2013 Jeep Grand Cherokee Overland
    2012 Jeep Grand Cherokee Overland Summit
    2007-2010,2012-2013 Jeep Grand Cherokee SRT8
    2012 Jeep Liberty Jet
    2008,2011-2012 Jeep Liberty Limited
    2011 Jeep Liberty Renegade
    2008,2011-2012 Jeep Liberty Sport
    2016 Jeep Wrangler 75th Anniversary
    2012-2018 Jeep Wrangler Rubicon
    2012-2017 Jeep Wrangler Sahara
    2012-2018 Jeep Wrangler Sport
    2016,2018 Jeep Wrangler Sport S
    2016 Jeep Wrangler Unlimited 75th Anniversary
    2018 Jeep Wrangler Unlimited Moab
    2012-2018 Jeep Wrangler Unlimited Rubicon
    2012-2018 Jeep Wrangler Unlimited Sahara
    2012-2018 Jeep Wrangler Unlimited Sport
    2016,2018 Jeep Wrangler Unlimited Sport S
    2018 Jeep Wrangler JK Rubicon
    2018 Jeep Wrangler JK Sahara
    2018 Jeep Wrangler JK Sport
    2018 Jeep Wrangler JK Sport S
    2018 Jeep Wrangler JK Unlimited Rubicon
    2018 Jeep Wrangler JK Unlimited Sahara
    2018 Jeep Wrangler JK Unlimited Sport
    2018 Jeep Wrangler JK Unlimited Sport S
    2012-2020 Ram 1500 Big Horn
    2012-2018 Ram 1500 Express
    2013-2020 Ram 1500 HFE
    2012-2020 Ram 1500 Laramie
    2014-2015 Ram 1500 Laramie Limited
    2012-2020 Ram 1500 Laramie Longhorn
    2015-2020 Ram 1500 Limited
    2014-2020 Ram 1500 Lone Star
    2012-2016 Ram 1500 Outdoorsman
    2013 Ram 1500 R/T
    2015-2020 Ram 1500 Rebel
    2012-2018 Ram 1500 SLT
    2014-2018,2020 Ram 1500 Special Service
    2012-2018 Ram 1500 Sport
    2012 Ram 1500 ST
    2012-2020 Ram 1500 Tradesman
    2012 Ram 1500 Tradesman HD
    2013 Ram 2500 Big Horn
    2012-2013 Ram 2500 Laramie
    2012-2013 Ram 2500 Laramie Longhorn
    2013 Ram 2500 Lone Star
    2012-2013 Ram 2500 Outdoorsman
    2012-2013 Ram 2500 Power Wagon
    2012-2013 Ram 2500 SLT
    2012-2013 Ram 2500 ST
    2013 Ram 2500 Tradesman
    Shipping Policy

    Shipping Policy Last Updated: April 2026

    We're committed to getting your order to you as quickly and transparently as possible. Here's everything you need to know about how we ship.

    Order Cancellations

    Once an order is placed, cancellations are not guaranteed as orders are sent to fulfillment quickly. If you need to cancel, contact us immediately at sales@berryperformancesales.com. If a cancellation is possible, the buyer is responsible for any transaction fees incurred. If the order has already shipped, it cannot be cancelled and must go through our standard return process.

    Processing Time

    In-stock orders are typically processed and shipped within 1–2 business days of receiving payment, unless otherwise noted on the product page. Orders placed on weekends or holidays will be processed on the next business day.

    Shipping Costs

    Shipping costs are calculated at checkout based on the shipping method selected, package weight and dimensions, and destination address. You can review all shipping costs before finalizing your purchase.

    Estimated Delivery Times

    Domestic orders typically arrive within 1–7 business days after shipment, depending on your location and the carrier. Please note that delivery times are estimates and are not guaranteed. Delays due to weather, carrier volume, or other circumstances beyond our control may occur.

    Tracking Information

    Once your order ships, you will receive a confirmation email with tracking information. Use this to monitor your package's progress. If your tracking has not updated within 48 hours of receiving your confirmation email, please contact us and we'll look into it.

    Shipping Address

    Please ensure your shipping address is accurate and complete before placing your order. If you realize an error after ordering, contact us immediately at sales@berryperformancesales.com — we will do our best to make the correction, but changes cannot be guaranteed once an order is in fulfillment. We are not responsible for orders shipped to incorrect or undeliverable addresses due to customer error.

    Please note: We are unable to ship to P.O. Boxes. Please provide a physical delivery address at checkout.

    Lost or Stolen Packages

    If your tracking shows your order as delivered but you have not received it, please take the following steps:

    • Check around your property and with neighbors
    • Confirm the shipping address on your order was correct
    • Contact the carrier directly with your tracking number

    If the issue remains unresolved, contact us at sales@berryperformancesales.com within 5 business days of the marked delivery date. We will work with you and the carrier to investigate. Berry Performance Sales is not responsible for packages confirmed as delivered by the carrier or for packages stolen after delivery.

    Damaged in Transit

    If your order arrives visibly damaged, please refer to our Returns & Refunds policy for instructions on how to report the issue. Carrier damage claims must be reported within 48 hours of delivery.

    International Shipping

    We do ship internationally! Because shipping costs, carrier options, and transit times vary significantly by destination, international orders require a custom quote prior to purchase. To request a shipping quote, contact us at sales@berryperformancesales.com with the following:

    • Your country and full delivery address
    • The item(s) you are interested in ordering

    We will respond with a shipping quote as quickly as possible. Please note that customs duties, import taxes, and any other fees charged upon delivery are the sole responsibility of the recipient and are not included in your shipping quote. We recommend checking with your local customs office before placing your order.

    Off-Road Use Disclaimer

    All products are sold for off-road use only unless otherwise specified. The buyer assumes full responsibility for installation and operation. Berry Performance Sales is not liable for any incidental, indirect, or consequential damages including engine failure, labor charges, or vehicle downtime resulting from the use of any product sold. By placing an order, you acknowledge and accept these terms.

    Questions?

    We're happy to help before, during, or after your purchase. Email: sales@berryperformancesales.com

    Berry Performance Sales reserves the right to update this policy at any time. Changes take effect immediately upon posting. It is the customer's responsibility to review the current policy at the time of purchase.

    Return Policy

    Returns & Refunds Last Updated: April 2026

    We want you to love what you ordered. If something isn't right, here's everything you need to know.

    30-Day Return Window

    You have 30 days from the date of purchase to initiate a return. After this window, we are unable to accept returns. We do not offer exchanges — all approved returns are refunded per the terms below.

    How to Initiate a Return

    To request a return, contact us at sales@berryperformancesales.com with your order number and reason for return. All returns must be approved by our team before any item is shipped back to us. Once your return has been approved, your item must be shipped within 10 days of approval. Items shipped without prior approval or outside this window will be refused and returned to sender.

    Return Conditions

    To be eligible for a return, items must be:

    • Unused and in original condition
    • In original packaging
    • Inclusive of all parts and accessories

    Custom ordered products are non-returnable. If you're unsure whether your item qualifies, contact us before purchasing.

    Once we receive your return, we will inspect the item before processing any refund. We reserve the right to deny or adjust your refund if the item is received in a condition that differs from what was originally shipped — including signs of use, missing parts, or damage that occurred after delivery.

    Fees to Know Upfront

    We believe in being transparent about costs:

    • Restocking Fee: 20% — deducted from all return refunds
    • Return Shipping: Buyer's responsibility on all standard returns
    • Cancellation (Installment/Payment Plan): 7% fee to cover transaction costs
    • Cancellation (Credit Card/PayPal): 3.5% processing fee

    Damaged or Defective Items

    If your order arrives damaged or defective, you must contact us within 48 hours of delivery at sales@berryperformancesales.com. Claims reported outside this window may not be eligible for resolution.

    When contacting us, please include:

    • Your order number
    • A description of the issue
    • Clear photos or video of the damage or defect

    If your item was damaged during shipping, this is handled as a carrier claim separate from our standard return process — we will assist you in filing that claim. Items confirmed to be defective due to a manufacturing or fulfillment error will have return shipping costs covered by Berry Performance Sales.

    Refunds

    Once we receive and inspect your return, refunds are processed within 3–5 business days back to your original payment method. You'll receive a confirmation once it's been issued.

    Questions?

    We're happy to help before, during, or after your purchase. Email: sales@berryperformancesales.com

    Berry Performance Sales reserves the right to update this policy at any time. Changes take effect immediately upon posting. It is the customer's responsibility to review the current policy at the time of purchase.

    Disclaimer

    All products are sold for off-road use only unless otherwise specified. Buyer assumes all responsibility for installation and operation. Seller is not liable for any incidental, indirect, or consequential damages — including engine failure, labor costs, or vehicle downtime — resulting from the use of any product sold.

    By making a purchase from Berry Performance Sales, you acknowledge and agree to abide by the terms and conditions of these Policies.

    For any questions or concerns, please contact us — we’re always happy to help.

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