Drivetrain› Automatic Transmissions and Components

Sonnax

2nd Gear "Corvette" Ratio Servo Kit

$61.10

SKU: 77701-04K

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Sonnax 2nd Gear "Corvette" Ratio Servo Kit is a performance servo kit designed for 4L60 (700-R4) and 4L60-E transmissions. It provides an increased apply area for improved holding power and firmer 1-2 and 3-4 shifts. This kit features D-rings in place of OE seal rings for better sealing during apply and release.
Show original supplier description
The Sonnax 2nd Gear "Corvette" Ratio Servo Kit is engineered to enhance the performance of 4L60 (700-R4) and 4L60-E transmissions. This direct replacement kit offers an increased apply area, resulting in improved holding power and noticeably firmer 1-2 and 3-4 shifts. The kit's servo piston utilizes upgraded Viton D-rings instead of standard seal rings, providing superior sealing during both apply and release phases. This design is particularly beneficial for high-performance applications or heavy-duty towing, offering greater reliability and responsiveness. Included in the kit are the piston, two Piston D-rings, the housing, and a housing O-ring, ensuring you have the necessary components for installation. This performance servo kit is also compatible with the Sonnax 4th Gear Super Hold dual servo kit (77767K). The material construction is aluminum, and it is designed for all 700R4/4L60/E models 1982 and up. It is suitable for RWD, AWD, and 4WD drive types.

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 Number77701-04K
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.

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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