Functionality
A 4L60E shift kit is an upgrade designed to improve the performance and reliability of GM’s 4L60E automatic transmission. It recalibrates key hydraulic circuits to correct issues like harsh or delayed shifting, TCC shudder, and premature clutch wear. Popular options include upgraded valves, springs, seals, and other components that can be installed with the transmission still in the vehicle. These kits often feature hardened parts and oversized check balls to enhance durability, delivering cleaner, firmer, and more consistent shifts for both daily-use and high-performance applications.
Transgo Shift Kits
Transgo offers multiple shift kits for the 4L60E. You would pick yours based on your application and desired outcome.
Guide to TransGo 4L60E Shift Kits: SK4L60E, HD2, PRO, and 3
If you’re upgrading or repairing a 4L60E transmission, TransGo offers several shift kits designed to improve durability, shift quality, and overall drivability. Each kit addresses different performance needs, from daily driving to high-horsepower builds. Understanding what each TransGo 4L60E shift kit provides helps you choose the right upgrade for your vehicle.
The TransGo SK4L60E kit is the standard repair and performance improvement option for the 4L60E. It corrects common transmission problems such as harsh or delayed shifts, 3–4 clutch burn-up, and torque converter shudder. This kit recalibrates the hydraulic circuits and installs without removing the transmission, making it ideal for daily drivers and general 4L60E repairs.
The TransGo 4L60E-HD2 shift kit is designed for drivers who want firmer shifts and stronger performance. It increases line pressure, improves shift response, and includes the optional Gear Command feature, which allows manual control of downshifts and gear holding on compatible models. This HD2 kit is well-suited for towing, performance street vehicles, and muscle car applications.
For high-power setups, the TransGo 4L60E-PRO shift kit delivers the most aggressive calibration available. It provides extremely firm, quick shifts and helps the 4L60E withstand higher torque levels. This kit is engineered for performance builds where reliability and shift precision are critical. The PRO kit is ideal for vehicles producing significant horsepower.
The TransGo 4L60E-3 kit provides full manual shift control from 1st through 4th gear. It eliminates the need for a transmission control module by using a vacuum modulator and boost valve to manage pressure. This kit is built for off-road vehicles, drag racing, and engine swap projects where automatic shifting is not required.
Choosing the right TransGo 4L60E shift kit depends on your driving needs: the SK4L60E is best for stock vehicles and everyday repairs, the HD2 is perfect for towing or spirited performance driving, the PRO kit is built for high-horsepower applications, and the 4L60E-3 is ideal for manual-shift or custom builds. With the right kit, your 4L60E transmission can deliver stronger performance, improved reliability, and better long-term durability.
Sonnax shift kit
The Sonnax Performance Pack for GM 4L60-E, 4L65-E and 4L70-E transmissions is a must-have for any heavy-duty vehicle and the very best foundation for high-performance racing. All components work together to carefully tune line pressure, accumulator pressure and shift calibration. It’s the ultimate way to get an impressive transmission that responds to throttle and increased load with quick, firm shifts.
Sonnax Transmission Sure Cure Kit SC-4L60E is a comprehensive reconditioning package for GM 4L60-E PWM units featuring the best Sonnax products developed to help rebuilders restore and enhance transmission performance. Sure Cure components are the same Sonnax parts sold individually to resolve common valve body complaints as well as other transmission problems. The high-quality Sonnax parts in each Sure Cure kit repair worn areas and protect the transmission against future damage. Plus, each kit comes with easy-to-read, step-by-step installation guide that covers the inspection and repair of the most critical areas of the valve body. Restore shift quality and reduce comebacks Repairs biggest trouble areas to reduce comebacks Includes step-by-step instructions for comprehensive valve/pump body restoration Get everything you need for restoring troublesome units in one place, at one cost NOTE: This kit is fully compatible with 95-later 4L60-E units with PWM/EC3 (electronically controlled capacity clutch) control. These can be identified by the 13-pin case connector, PWM/TCC solenoid and PWM pump (five solenoids). All components in this kit are compatible 9394 non-PWM units EXCEPT the TCC apply valve 77805E-K installed in the pump. These units can be identified by the 12-pin case connector, only having a 3-2 solenoid in valve body (four solenoids).
Superior K4L60E shift kit
The Superior K4L60E shift kit is a performance and reliability upgrade designed to correct common hydraulic issues in the GM 4L60E transmission. It improves shift feel, reduces clutch slippage, and enhances overall durability by stabilizing pressure control and optimizing valve body function. The kit includes upgraded springs, valves, and components engineered to prevent wear in high-mileage units. Ideal for both daily drivers and mild performance builds, the Superior K4L60E kit delivers smoother, more consistent shifting and longer transmission life.
