STL010 8L90 2016 & Up Sure-Cool System
The STL010 Sure-Cool System is engineered specifically for 2016 and newer 8L90 transmissions to enhance performance, protect internal components, and maintain optimal thermal control. With features like full-time cooler flow, immediate cooler fill, and a built-in safety bypass, this system helps manage temperature, fluid quality, and shifting reliability, preserving clutches, torques, valves, and the entire transmission under demanding conditions.
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Efficient Cooling & System Protection
Proper cooling is essential to preserving performance and extending transmission life. The Sure-Cool System ensures the 8L90’s fluid temperature stays within its ideal operating range, helping to prevent heat-related damage and maintain consistent internal pressure. Stable temperatures mean longer-lasting fluid quality, smoother gear transitions, and improved operating efficiency under all driving conditions.
Full time cooler flow
Reduced average operating temperatures
Reduced risk of overheating
Reduced risk of planetary damage
By keeping fluid temperatures lower and more stable, the system also extends ATF life, promoting better efficiency, control, and longevity throughout the gear and clutch circuits.
Rapid Fill & Warm-Up Optimization
The Sure-Cool System supports immediate fluid circulation through the cooler circuit, allowing the transmission to achieve proper lubrication and pressure control faster than stock systems. This feature eliminates the traditional warm-up cycle, ensuring that clutch packs, valves, and torque converter circuits receive adequate fluid volume from startup, delivering consistent performance, protection, and smooth shifts right from the first gear engagement.
These features prevent delay in fluid delivery to the torque converter and valve body circuits, ensuring robust lubrication, pressure control, and consistent shift quality from the moment the transmission is operated, even under cold conditions.
Built-In Safety & Reliability
The integrated safety features of the Sure-Cool System protect against internal restrictions or fluid flow interruptions that can compromise performance. By maintaining steady hydraulic pressure and temperature balance, the system safeguards the planetary gear sets, clutches, and converter circuits during demanding operating conditions, ensuring consistent reliability and long-term transmission health.
Whether under high load, steep climbs, or temperature extremes, the bypass preserves cooler flow if restrictions or blockages arise, maintaining pressure control, guarding against valve-chatter, and protecting clutches and internal gears from damage.
Why Choose This System for High-Performance 8L90 Use
Designed with both performance enthusiasts and everyday drivers in mind, the STL010 Sure-Cool System enhances transmission efficiency and gear control under load. By maintaining consistent fluid temps and preventing overheating, it reduces wear across internal components while ensuring the 8L90’s gear ratio, clutch timing, and valve operation stay precise. This leads to better drivability, improved performance, and a longer service life for your transmission.
Designed for performance driving and heavy-duty applications while maintaining compatibility with daily driving demands
Improves thermal stability, optimizing gear ratio response, clutch modulation, and speed control under load
Long-term reliability in terms of fluid quality, minimizing oxidation and breakdown due to heat
Seamless integration with your existing transmission, often avoiding significant modifications or compromise to original valve or passage routing
Frequently Asked Questions
Will adding the Sure-Cool System affect shift feel or clutch pressure control?
No. When installed correctly, the system supports consistent pressure across clutches and valves. By keeping transmission fluid in optimal temperature ranges and ensuring constant cooler flow, it helps maintain more stable control pressure and shift quality, without interfering with your valve or line pressure balance.
Does this system help protect planetary gears and torque converter internals?
Yes. Lowering operating temperatures and avoiding fluid degradation reduces risk of thermal stress and breakdown of internal lubricity. That promotes healthier gear and clutch surfaces and helps preserve torque converter efficiency and reliability.
Is the built-in safety bypass a fallback or permanent path?
It’s a fallback. Under normal conditions, the cooler flow path is active. If the system senses a blockage or excessive restriction, the safety bypass opens automatically to maintain fluid circulation, protect valves, and avoid pressure starvation in your transmission.
Will this system improve my transmission’s efficiency or longevity?
Yes. Reduced operating temperatures slow down the breakdown of ATF, help maintain viscosity and control qualities, and reduce wear on valves, clutches, and gear interfaces. Over time, this contributes to more reliable performance, better efficiency, and extended lifespan.
Do I need to replace or alter existing transmission components (valves, lines, cooler) to install this system?
Generally no. The Sure-Cool System is designed to integrate into the 8L90 setup without requiring dramatic rerouting or replacement of major valve body architecture. However, proper installation, line routing, and ensuring clean fluid passages are critical. Always inspect cooler lines, valve bodies, and fluid passages during installation to ensure the system operates effectively.
