Trans Cooler Thermal Bypass Valve - Fits GM Trucks/SUVs

In this review the Trans Cooler Thermal Bypass Valve is evaluated as a direct-replacement thermal bypass for select GM trucks and SUVs. The bottom line: this valve is for owners who need a reliable way to regulate coolant flow to the transmission cooler so the transmission reaches and maintains proper operating temperature. It performs the single most important job expected of it - modulating coolant flow by temperature - and does so with a simple aluminum assembly that replaces factory part numbers 86774933 and 85585333.

Key Features

• Vehicle compatibility: Covers a broad range of GM models and years so buyers can easily find a fit for Cadillac CT6, Escalade, Chevrolet Silverado, Suburban, Tahoe, and GMC Sierra and Yukon models listed in the product description.
• Thermal regulation: The bypass valve regulates coolant flow to the transmission cooler based on temperature, helping prevent overcooling or overheating of transmission fluid.
• Improved engine warm-up: By directing coolant appropriately, it helps the engine reach optimal temperature faster during cold starts, which can improve transmission operation and shift performance.
• Durable construction: Made of aluminum with corrosion and wear resistance to provide long service life in the cooling system environment.
• OE replacement fit: Designed to replace factory part numbers 86774933 and 85585333 so it integrates into existing cooling and transmission plumbing without major modification.

Who It's For

This valve is best for owners of the specific GM vehicles listed who are experiencing transmission fluid temperature issues or who want to restore correct coolant routing after a failed original valve. It is also suitable for mechanics and DIYers who prefer a direct-replacement part that uses established part numbers.

It is not intended for vehicles outside the listed model-year ranges or for buyers who need a custom cooling solution; those users should consult a specialist or source a model-specific component. Buyers seeking a valve with integrated electronic sensors or adaptive control should look elsewhere.

Pros & Cons

Pros

• Direct replacement for factory part numbers 86774933 and 85585333, simplifying installation for compatible models.
• Helps maintain proper transmission temperature, which customers reported improves transmission temperature control.
• Aluminum construction offers corrosion and wear resistance for longer service life.

Cons

• Installation feedback is mixed; some users find it very easy while others may need moderate mechanical skill or professional help.

Specifications

Our Verdict

The Trans Cooler Thermal Bypass Valve is a solid, practical replacement for owners of supported GM models who need dependable coolant flow control for the transmission cooler. Its aluminum construction and OE part number compatibility make it good value for repairs that restore proper transmission temperature management, though installation may require basic mechanical skill or shop assistance.

Frequently Asked Questions

Which vehicles does this valve fit?
It fits specified Cadillac CT6 and Escalade years and a range of Chevrolet Silverado, Suburban, Tahoe and GMC Sierra, Yukon years listed in the product description.

What does the bypass valve do?
It regulates coolant flow to the transmission cooler based on temperature to avoid overcooling or overheating and to help the engine warm up faster.

Is installation difficult?
Installation is straightforward for experienced DIYers and mechanics, though some customers report mixed ease-of-installation experiences and may prefer professional installation.