Tru-Cool, Transmission Oil Cooler Cold Weather Thermostat , Universal Fit

Tru-Cool External Thermal Bypass Assembly for Cold Weather

Protect your transmission from the dangers of "over-cooling" in freezing climates with the Tru-Cool External Thermal Bypass Assembly. Specifically designed for vehicles operating in temperatures below 32¡F (0¡C), this bypass valve ensures your transmission fluid reaches its optimal operating temperature as quickly as possible. In cold weather, transmission fluid becomes thick and viscous, which can lead to poor lubrication and increased wear. This assembly allows the fluid to bypass the external cooler until it warms up, protecting your drivetrain and improving shifting performance in winter conditions.

The Tru-Cool 4739P6 is a high-precision thermal valve that remains closed when the fluid is cold, directing it back to the transmission. As the fluid temperature reaches approximately 180¡F, the bypass begins to open, and it is fully open by 205¡F, allowing the external cooler to perform its job during high-stress or high-temperature operation. Engineered by Long Manufacturing, this "no-fail" component is the perfect insurance for heavy-duty trucks, towing rigs, and performance vehicles that see year-round use.

Features

• Cold Weather Optimization: Essential for vehicles in climates reaching 32¡F and below to prevent fluid thickening and lubrication lag.
• Rapid Warm-Up: Directs cold fluid away from the cooler, allowing the transmission to reach efficient operating temperatures faster.
• Thermal Precision: Starts activating at 180¡F and provides full cooling flow by 205¡F for balanced thermal management.
• Universal Compatibility: Designed to work with any external transmission cooler using 5/16", 3/8", or 11/32" fluid lines.
• Reliable Performance: A passive, mechanical design with no electronics to fail, ensuring consistent operation in the harshest environments.
• Durable Construction: Built by Long Manufacturing (Tru-Cool) to meet rigorous performance and off-road standards.
• Easy Installation: Slices into existing cooler lines, making it a simple but effective upgrade for any auxiliary cooling system.

Spec

• Brand: Tru-Cool (Long Manufacturing)
• Part Number: 708-4739P6 / 4739P6
• Activation Temp: Starts at 180¡F (Fully open at 205¡F)
• Line Size Compatibility: 5/16", 3/8", and 11/32" Lines
• Operating Range: Optimized for sub-32¡F (0¡C) environments
• Product Type: External Thermal Bypass Valve
• Application: Universal for Automatic Transmissions