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Drivetrain› Automatic Transmissions and Components

Sonnax

Oversized Lockup Relay Valve Kit

$112.54 $66.64 Save $45.90

SKU: 37740-11K

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Sonnax Oversized Lockup Relay Valve Kit is engineered to address common issues in U341E and U341F transmissions, including TCC apply and release problems, inadequate lubrication, and overheating. By restoring critical clearances within the transmission, this kit promotes renewed TCC control and operation. The kit contains an oversized relay valve, plunger valve, spring, and end plug, designed as direct replacements for OE components. Installation involves removing the OE parts and installing the new Sonnax components to recondition the valve body. Specific tools may be required for proper installation, and instructions are available from Sonnax. This kit is specifically designed for Toyota/Lexus vehicles equipped with U341E and U341F transmissions. It aims to resolve concerns such as no lockup, slipping lockup, or a TCC stuck on, as well as TCC codes that may arise from worn components.

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

BrandSonnax
Part Number37740-11K
CategoryDrivetrain
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

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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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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