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Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit - MMTC-L5P-TBVFF

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MSRP: $122.34
$119.71
(You save $2.63 )
SKU:
MISMMTC-L5P-TBVFF
UPC:
840197710609
Current Stock:
1
MPN:
MMTC-L5P-TBVFF
5 customers are viewing this product
Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit - MMTC-L5P-TBVFF

Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit - MMTC-L5P-TBVFF

MSRP: $122.34
$119.71
(You save $2.63 )
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+ 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 add even more heat dissipation. This 2017+ 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.

This Part Fits:

YearMakeModelSubmodel
2021ChevroletSilverado 2500 HDCustom
2017-2021ChevroletSilverado 2500 HDHigh Country
2017-2021ChevroletSilverado 2500 HDLT
2017-2021ChevroletSilverado 2500 HDLTZ
2017-2021ChevroletSilverado 2500 HDWT
2017-2021ChevroletSilverado 3500 HDHigh Country
2017-2021ChevroletSilverado 3500 HDLT
2017-2021ChevroletSilverado 3500 HDLTZ
2017-2021ChevroletSilverado 3500 HDWT
2020-2021GMCSierra 2500 HDAT4
2017-2021GMCSierra 2500 HDBase
2017-2021GMCSierra 2500 HDDenali
2017-2021GMCSierra 2500 HDSLE
2017-2021GMCSierra 2500 HDSLT
2020-2021GMCSierra 3500 HDAT4
2017-2021GMCSierra 3500 HDBase
2017-2021GMCSierra 3500 HDDenali
2017-2021GMCSierra 3500 HDSLE
2017-2021GMCSierra 3500 HDSLT
Returns Policy

You may return most new, unopened items within 30 days of delivery for a full refund. All Products must be sent back for return in New and Original Packaging.

EXCEPTIONS:Products shipped by truck freight, special orders, and some non-stocked items are all non-returnable. All Open-Box/Closeout items are sold AS-IS and are not returnable. Used, damaged, installed or altered items are non-returnable. No exceptions. Please contact the manufacturer directly for warranty issues.

If you receive incorrect or mis-shipped items in error (Ooops! We messed up!), it is still up to you to notify us within 10 business days so we can get the correct items re-shipped in a timely manner. (Prices, parts and in-stock items change often so we apologize in advance, but we must insist you open your shipments as they are delivered to see if they are correct.) If you fail to notify us within this timeframe, you will have to follow the normal 30 day return policy. Mis-shipped or incorrect items are not our responsibility after 30 days.

We are not responsible for damage claims when items are shipped to freight forwarding companies or other intermediaries and then forwarded on to another destination. The customer assumes all responsibility for the items they forward.

Returns Procedure

Contact WunderCarParts at 1-888-986-3373.Prepare your package in original packaging, with all parts, pieces and paperwork that were included when delivered.Return your item via your preferred shipping provider.

NOTE: If return is due to an improperly or incorrectly shipped item from WunderCarParts, your label will be freight-prepaid. All other returns are not pre-paid.

Upon receipt of your return, WunderCarParts will inspect your item and issue a refund according to WunderCarParts’s refund & restocking fee policy. Please ask prior to returning your part if a restocking fee is likely to apply. Some parts have a required 15-35% restocking fee based on manufacturer policies which we will charge to you and deduct from your refund or in-store credit. Refunds will take up to 10 days to process.

CORE Return Policy

All cores are due within 30 days of purchase. You must follow the core return directions emailed to you upon purchase. Once your core return has been processed by the manufacturer, you will receive a full in-store credit immediately or full refund to the original credit card within 7-10 days for cores in usable condition, no exceptions. After 60 days of purchase, cores returned in good condition may be eligible for a full in-store credit or a refund less a 20% late fee. Expired cores in usable condition that are over 90 days from date of purchase may be eligible for a partial in-store credit only, less a 20% late fee.

** You are responsible for all core return shipping back to the manufacturer, along with insurance and tracking to verify the core arrived at the manufacturer. The manufacturer will inspect your core and make core credits based on their findings. If a core is un-buildable, they will adjust or deny your core accordingly. Core credits are NOT guaranteed. WunderCarParts is not responsible for delayed credits or lost/damaged cores.

Shipping Policy

All items shipped from WunderCarParts ship UPS or FedEx ground for free to the Lower 48 States.* Some items that are overweight, larger than normal, or special order, may incur additional freight charges. We strive to maintain accurate rates on our website, but at times, certain products will have modified freight, and will incur other charges, if this occurs, WunderCarParts will contact you to discuss the differences in costs or arrange a different shipping method if possible. *Excludes: Alaska/Hawaii, US Protectorates, APO/FPO, PO Box

Most of our items are shipped “Signature required”, requiring an adult to sign for the package upon delivery. If a shipment is refused or non-deliverable and is returned to us, the customer will be responsible for any re-delivery charges and restocking fees. WunderCarParts is not responsible for addresses deemed undeliverable or packages redirected for pick-up at an alternate location by the carrier.

UPS and FedEx maintain the option to REQUIRE a signature at the time of delivery, regardless of the recipient’s request to leave the package at the door. We make every effort to ship as requested by the customer, but the carrier reserves the right (as the responsible party) to make any changes based on the value of the shipment or other liability considerations.

We do not ship internationally at this time. However, you can purchase from our ebay store and use ebay global shipping.Ebay Store Ink: https://www.ebay.com/str/wundercarparts

If an item is inadvertently backordered, or must be drop shipped from a manufacturer, we will notify you via email or phone call once our warehouse notifies us. Please make sure we have a valid Email and Phone Number for you.

Some items are special order or come directly from the manufacturer. Delays in processing times or shipping can occur for these items. Your patience is appreciated.

Periodically, a part may be discontinued or temporarily unavailable that is listed on our website due to changes or production issues by the Manufacturer. We make every attempt to maintain current information and stock levels, but are not responsible for any manufacturing delays.

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