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

Fits 2017-2019 6.6L Duramax V8 (L5P)

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gain
protects power, no gain
price
$99.95
at Battle Born Off Road
install
3/5 difficulty · varies by part
Buy at Battle Born Off Road

Transmission parts here are about holding torque and keeping fluid temperature down, which is what kills automatics. This one is the Mishimoto Mishimoto 2017+ GMC 6.6L Duramax L5P Transmission Thermal Bypass Valve Kit, listed to fit the 2017-2019 GMC Sierra 2500HD/3500HD with the 6.6L Duramax V8 (L5P).

why this one — Towing heat is the usual reason to buy. Check what your truck already has before adding a cooler or pan. Battle Born Off Road lists it at $99.95, and the fitment above is what the listing itself states, not a guess.

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No published gain figure for this part, and nothing here is a guarantee. Price is a list price and can lag the retailer; confirm at checkout. See our affiliate disclosure.

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