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

Mishimoto
MISMMTC-L5P-TBV
840197710616
Transmission Coolers
5 Units In Stock - Ships Next Business Day
$ 163.00 $ 147.95
$ 147.95

SKU: MMTC-L5P-TBV | UPC: 840197710616

Mishimoto 2017+ Chevrolet/GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit

Replace the failure-prone stock thermal bypass valve in your 2017+ Chevrolet Silverado and GMC Sierra HD trucks with L5P Duramax diesel. This Mishimoto kit ensures transmission fluid reaches the cooler for effective heat management during towing and heavy loads. CNC-machined aluminum design delivers reliable performance with faster warm-up and constant cooling options.

Key Features

  • CNC-Machined Aluminum Body: Black anodized finish resists corrosion and includes cooling fins for extra heat dissipation from transmission fluid.
  • Fully Serviceable Thermostat: Allows quick warm-up in cold weather while opening reliably at operating temperature to direct fluid to the cooler.
  • Thermostat Bypass Option: Install for unrestricted flow in hot climates or extreme towing to maintain low temperatures at all times.
  • Improved Internal Passages: Strategically machined channels increase fluid flow over stock for better cooling efficiency in Allison 1000/10L100 transmissions.
  • Mishimoto Lifetime Warranty: Backed by durable construction to protect your transmission investment for the long haul.

Product Notes

  • Direct replacement for OEM Allison thermal bypass valve with no modifications needed.
  • Kit includes valve thermostat bypass hardware and O-rings for complete installation.
  • MPN MMTC-L5P-TBV weighs 0.95 lbs and ships in a compact package.

Installation Notes

  • Professional installation recommended.
  • Bolt-on design fits directly in stock transmission location on Allison 1000/10L100.
  • Basic hand tools required includes all gaskets and fittings for leak-free setup.

This Part Fits

Year Make Model Submodel
2017-2021 Chevrolet Silverado 2500 HD Custom
2017-2021 Chevrolet Silverado 2500 HD High Country
2017-2021 Chevrolet Silverado 2500 HD LT
2017-2021 Chevrolet Silverado 2500 HD LTZ
2017-2021 Chevrolet Silverado 2500 HD WT
2017-2021 Chevrolet Silverado 3500 HD LT
2017-2021 Chevrolet Silverado 3500 HD LTZ
2017-2021 Chevrolet Silverado 3500 HD WT
2017-2021 GMC Sierra 2500 HD Base
2017-2021 GMC Sierra 2500 HD Denali
2017-2021 GMC Sierra 2500 HD SLT
2020-2021 GMC Sierra 2500 HD AT4
2017-2021 GMC Sierra 3500 HD Base
2017-2021 GMC Sierra 3500 HD Denali
2017-2021 GMC Sierra 3500 HD SLE
2017-2021 GMC Sierra 3500 HD SLT
2020-2021 GMC Sierra 3500 HD AT4

Why Choose Mishimoto?

  • Proven track record in diesel performance cooling for Duramax owners.
  • Precision engineering matches OEM specs while enhancing flow and reliability.
  • Direct-fit solutions tested for heavy-duty towing and daily driving.

Frequently Asked Questions

  • Q: Will this fit my 2017-2021 Silverado 3500HD with L5P Duramax?
    A: Yes it fits all listed Chevrolet Silverado 2500HD and 3500HD models with 6.6L L5P and Allison transmission including LT LTZ and WT trims.
  • Q: What material is the valve made from?
    A: High-strength CNC-machined billet aluminum with black anodized coating for corrosion resistance and added cooling.
  • Q: What warranty comes with this kit?
    A: Mishimoto Lifetime Warranty covers defects in materials and workmanship for as long as you own the vehicle.

Shipping & Handling

  • Method: UPS Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Secure Mishimoto box 7.5 x 5.5 x 2.5 inches
  • Weight: 0.95 lbs

Request For Information

Have questions about Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit? Fill out the form below and we'll get back to you by the next business day.
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