Sale

Superior Transmission Parts

Thermal Bypass and Flow Control Valve

$48.50 $30.28 Save $18.22

SKU: STL020

In Stock
In Stock
Ships by Aug 31
Free Shipping over $200
$100 Minimum Order
30 Days Return

Description

The Superior Transmission Parts STL020 Sure~Cool® Thermal Bypass / Flow~Control valve is a USA-made upgrade for various automatic transmissions. This system ensures full-time cooler flow, providing immediate cooler fill and an accurate fluid level check without needing a warm-up cycle. It is recommended as preventive maintenance during transmission rebuilds or routine service. This valve actively manages transmission fluid temperature by bypassing the cooler when cold and ensuring constant flow when warm. Features include a built-in safety bypass, reduced average operating temperatures, and increased ATF life. Compared to factory thermostatic pellet-style systems, the STL020 significantly reduces the risk of overheating and planetary gear damage. Compatible transmissions include the Ford 4R70, 4R75, 6F35, 6F50, 6F55, 6R80, and 6R90. It also works with late 2021-up GM 10L80 and 10L90 transmissions. Instructions are included with the part.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandSuperior Transmission Parts
Part NumberSTL020
CategoryDrivetrain

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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