Transmission Cooler Hose Assembly for Silverado and Sierra

Dorman 724-133 is an automatic transmission oil cooler hose assembly for select Chevrolet Silverado 1500 and GMC Sierra 1500 trucks. It replaces the factory crimped connection with a threaded connection to simplify service and help maintain a secure, leak-resistant seal for transmission fluid flow.

Built for inlet and outlet use, this molded assembly is a direct-fit service solution for 2009-2013 Chevrolet Silverado 1500 and 2009-2013 GMC Sierra 1500 applications. If you are replacing a leaking or rusted transmission cooler line on a Silverado 1500 or Sierra 1500, Dorman 724-133 provides a serviceable OE FIX design.

Key Features

• Automatic transmission oil cooler hose assembly for inlet and outlet service
• OE FIX design replaces the factory crimped connection with a threaded connection
• Helps restore proper transmission fluid routing and sealing
• Molded assembly with flexible construction for vehicle-specific routing
• Black and silver hose and housing finish
• Rated for -40 Deg. F to 329 Deg. F operating temperatures
• Maximum working pressure: 250
• Part number 724-133

Detailed Description

Dorman 724-133 is engineered for Chevrolet Silverado 1500 and GMC Sierra 1500 trucks that use an automatic transmission oil cooler hose assembly at the inlet and outlet. The original design on these trucks uses crimped connections between the lines and bypass valve, which can make a leak or line failure expensive to repair because the full assembly is often replaced. This Dorman OE FIX assembly changes that connection to a threaded design for easier serviceability while maintaining a secure seal for transmission fluid control. The molded hose assembly measures 54 inches and includes fittings and a gasket or seal for installation. Part number 724-133 is a practical replacement when corrosion, fatigue, or leakage affects the transmission cooler line assembly.

This part cross-references 20835129 for the same application.

What It Helps Fix

• Transmission fluid leaks at the cooler line assembly
• Rust-related failure in the original cooler hose or line
• Fatigue or cracking in aging transmission cooler plumbing
• Poor sealing at the bypass valve connection
• Restricted or unreliable transmission fluid flow through damaged lines

Installation Notes and Tips

Verify vehicle application before installation. This assembly is listed for 2009-2013 Chevrolet Silverado 1500 and 2009-2013 GMC Sierra 1500 models at the inlet and outlet position. Inspect the mating transmission cooler connections, bypass valve area, and surrounding lines for corrosion or damage before installing Dorman 724-133. Confirm the hose routing matches the original layout and ensure all sealing surfaces are clean for proper fluid retention.

Quality Assurance

Dorman designs OE FIX replacement parts to address common factory service issues with improved serviceability. This transmission cooler hose assembly is built to support secure fluid sealing and dependable fitment for the listed Silverado 1500 and Sierra 1500 applications.