Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P
Mishimoto Thermal Bypass Valve Kit for 2017+ GMC 6.6L Duramax L5P

Mishimoto Full-Flow Thermal Bypass Valve Kit - Chevrolet / GMC 6.6L Duramax L5P 2017-2021

Mishimoto SKU: MISMMTC-L5P-TBVFF
Price
9% OFF
In Stock – Ready to Ship
Make sure this fits your vehicle Select your vehicle to confirm fitment before you order. Check
Shipping calculated at checkout.

The Mishimoto full-flow thermal bypass valve kit replaces the failure-prone factory bypass valve on the Chevrolet/GMC 6.6L Duramax L5P with the Allison 1000 transmission. The stock valve withholds transmission fluid from the cooler until operating temperature, and its thermostat can fail closed, starving the cooler and overheating the transmission. This CNC-machined billet aluminum full-flow valve eliminates the thermostat entirely, pumping fluid through the cooler the moment the truck starts for constant cooling, ideal for hot climates, heavy towing, or extreme driving. Black anodized, backed by the Mishimoto Lifetime Warranty.

Specifications

Type Full-flow transmission thermal bypass valve kit
Transmission Allison 1000
Material CNC-machined billet aluminum, black anodized
Function Full-flow (no thermostat); constant cooler flow
Part Number MMTC-L5P-TBVFF
Warranty Mishimoto Lifetime Warranty

This part fits:

Year Make Model Submodel
2017-2021 Chevrolet Silverado 2500 HD / 3500 HD 6.6L Duramax L5P (all trims)
2017-2021 GMC Sierra 2500 HD / 3500 HD 6.6L Duramax L5P (all trims)

Shipping

  • Orders placed before 3 PM EST typically ship the same business day. Larger items ship within 1 to 3 business days.
  • Standard, expedited, and overnight options at checkout.
  • Oversized items ship by freight and take longer.
  • Special order items follow a lead time we confirm with you individually before the order is committed.
  • Backordered items ship as soon as stock lands. Lead times are manufacturer estimates and can change. Contact us for current ETAs.
  • Need to cancel? Email us right away. Cancellations are not guaranteed once an order is in process. In-stock orders cancel free before they ship; a 6% fee applies only to confirmed backorders and special orders.
  • International orders: prices do not include VAT, duties, or import fees. Your country charges these at import and they are the buyer’s responsibility.

Returns

  • 30 days from delivery to request and ship back a return on new, uninstalled items in original packaging with all hardware.
  • Standard returns: 8% restocking fee on the item price before tax and shipping. Shipping is not refunded in either direction. All waived if the item is defective or we made the error.
  • Fitment guaranteed: select your vehicle above, or confirm fitment with us in writing before you order. If the part shows as a fit and it is wrong, the return is on us, even after installation. Otherwise, installed or used parts cannot be returned.
  • Final sale: special orders, coilovers, electronics, engine internals, turbochargers, superchargers and turbo kits, unless defective or we sent the wrong item.
  • Product images may be representative. The SKU and specifications in the listing are what ships.
  • Email us for return authorization before shipping anything back.

Full details: Shipping Policy · Returns & Refunds · Warranty
You may also like
Recently viewed