6L80/6L90/8L90 Transmission Sure Cool STL010 Thermal Upgrade Kit for 5.3L/6.2L V8/3.0L V6 Twin Turbo Chevrolet GMC Cadillac (2015-2021)

Product Overview

This 6L80/6L90/8L90 Transmission STL010 Thermal Upgrade Kit is a direct bolt-on cooling enhancement accessory engineered for GM 6-speed and 8-speed automatic transmissions. It integrates innovative rapid cooling and precision oil detection technology to solve common transmission overheating and oil circulation lag issues. The built-in safety bypass system prevents excessive pressure damage to the gearbox during operation. Equipped with high-quality integrated sealing gaskets, it eliminates oil leakage risks and improves overall transmission reliability. It optimizes heat exchange efficiency to reduce thermal fatigue, perfectly upgrading the factory cooling system for enhanced durability and stable performance.

Ideal For

• Towing and Hauling: Delivers stable high-load heat dissipation to prevent transmission overheating during heavy towing and cargo hauling, avoiding power attenuation and gearbox damage caused by sustained high temperatures.
• Daily Driving: Optimizes transmission oil circulation efficiency, eliminates preheating waiting time, ensures real-time accurate oil level detection, and maintains consistent daily driving transmission performance.
• Off-Road Use: Enhances heat dissipation stability under low-speed high-torque off-road conditions, effectively resists overheating risks and protects transmission fluid and internal components during harsh driving.
• Commercial Vehicles: Improves transmission durability for long-distance and high-frequency operating commercial GM vehicles, reducing overheating-related maintenance failures and downtime losses.
• Engine Performance Upgrades: Serves as a critical supporting upgrade for tuned and modified engines, matching increased power output to avoid transmission thermal overload and performance bottlenecks.
• Long-Term Vehicle Ownership: Reduces transmission thermal attenuation and oil aging speed, lowers long-term repair and fluid replacement costs, and extends the overall service life of the transmission assembly.

Core Advantages

• Stable Transmission Performance: Reduces transmission operating temperature by up to 20% compared with factory systems, eliminates thermal attenuation, and maintains consistent shifting performance under all driving conditions.
• Improved Operational Efficiency: Features instant oil cooling and second-level rapid coolant filling, shortens start-up waiting time, and accelerates transmission oil circulation to improve overall vehicle operation efficiency.
• Precision Oil Level Monitoring: Supports cold start one-click oil level detection without preheating, realizes real-time monitoring of transmission oil status, and ensures optimal transmission operating conditions.
• Enhanced Leak-Proof Reliability: Comes with premium integrated bypass gaskets with factory-matched one-piece sealing structure, effectively prevents ATF oil leakage and improves long-term operational stability.
• Load Overheat Protection: Strengthens high-load heat dissipation capacity, avoids overheating failures under extreme working conditions, and extends the service life of transmission fluid and internal components.
• Direct Bolt-On Installation: Fully compatible with original factory transmission structure, no cutting or drilling required, plug-and-play installation saves modification time and cost.
• Complete All-In-One Kit: Includes all required gaskets and hardware accessories, no additional parts purchase needed for full installation.

Technical Specifications

• Material: High-strength heat-resistant aluminum alloy + premium rubber sealing material
• Finish: Anti-corrosion and heat-dissipating anodized finish
• Weight: 1.8 lbs
• Dimensions: 8.5 x 6.2 x 3.1 inches
• Warranty: 1 Year Limited Warranty against manufacturing defects

Why Choose EGR Performance

• Premium Quality Materials: Adopts heat-resistant and pressure-resistant aluminum alloy and high-elasticity sealing rubber, resistant to high temperature aging and deformation for long-term stable use.
• Precision Engineering: CNC precision machined to match factory mounting points perfectly, ensuring seamless fit and consistent cooling performance.
• Rigorous Testing: Undergoes high-temperature, high-load and long-duration bench testing to verify overheat protection and leak-proof performance for extreme driving scenarios.
• Dedicated Customer Support: Email us at service@egrperformance.com for professional technical and compatibility consultation.
• Fast Shipping from USA Warehouse: Local US inventory supports fast delivery and short transit time for all orders.
• 1 Year Limited Warranty: Covers all manufacturing defects to guarantee your purchase quality and use experience.

Troubleshooting and Problem Solving

Common Issues After Installation

• Check Engine Light activation due to incomplete system reset
• Minor rough idle caused by unadapted oil circulation
• Temporary reduced power during initial system adaptation
• Slow coolant filling caused by unconnected pipeline
• Oil leakage from loose gasket or hardware installation

Error Code Solutions

• P0218: Transmission Over Temperature Condition - Check cooling pipeline blockage, confirm full installation of upgrade kit, and clear residual high-temperature data.
• P0841: Transmission Fluid Pressure Sensor Circuit Malfunction - Inspect pipeline connection tightness and reset vehicle control system.
• P2769: Torque Converter Clutch Circuit Malfunction - Verify gasket sealing and hardware fastening status, test transmission oil circulation.

How to Reset Check Engine Light After Installation

1. Turn off the vehicle engine and disconnect the battery negative terminal for 5-10 minutes.
2. Reconnect the battery and start the vehicle to idle for 10 minutes without load operation.
3. Drive the vehicle at a constant speed for 5-10 miles to complete system self-adaptation.
4. Use an OBD scanner to clear residual fault codes and confirm normal system operation.

What to Do If Your Vehicle Loses Power After Installation

• Check if all cooling pipelines are fully connected and no blockage exists in the circulation system.
• Inspect gasket installation position to eliminate air leakage or oil leakage affecting pressure balance.
• Confirm transmission fluid volume meets factory standard, avoid excessive or insufficient fluid.
• Complete vehicle system reset and perform road test to verify power recovery.

Long-Term Maintenance Tips

• Regular Inspection: Inspect cooling pipeline connections and gasket sealing status every 5,000 miles to check for oil leakage or loose fittings.
• Routine Maintenance: Clean the cooling system circulation channel and remove dust and oil dirt every 10,000 miles to ensure optimal heat exchange efficiency.
• Wear Parts Replacement: Replace sealing gaskets every 30,000 miles to maintain long-term leak-proof performance of the kit.
• Hardware Check: Tighten all installation bolts and check pipeline aging status every 15,000 miles to avoid loosening and failure.
• Storage Tips: Store the spare kit in a dry and cool environment, avoid high-temperature and humid places to prevent rubber gasket aging.
• Warranty Reminder: Following these maintenance guidelines will keep your 1 Year Limited Warranty valid