Hayden 390 Automatic Transmission Oil Cooler Line Connector

Transmission Oil Cooler Line Connector Kit

Hayden 390 is an oil cooler install kit for automatic transmission applications that use male inlet and outlet connections. Built from steel with a gold finish, this performance-rated fitting kit is used to service transmission cooler line connections on a wide range of Chevrolet, GMC, Cadillac, Ford, Jeep, Pontiac, Buick, Oldsmobile, and Isuzu vehicles.

This part cross-references Dorman - HELP (e.g., 77026, 79830) for the same application.

Key Features

• Hayden Cooler Inst.Kit, part number 390
• Automatic transmission oil cooler line connector kit
• Steel construction with gold finish
• Male inlet and male outlet configuration
• Round connector shape, w/o bracket
• Performance rated for transmission service applications
• Gasket and seals not included

Product Details

Hayden 390 is a transmission fitting kit used on vehicles with automatic transmission oil cooler line connections, including applications that call for 5/8"-18 inverted flare fittings or snap-in style transmission line fittings. The Hayden Cooler Inst.Kit line is focused on service parts for transmission cooling systems, and this connector kit follows that purpose with a steel body, round profile, and compact dimensions for underhood routing. Common search terms for this part include automatic transmission oil cooler line connector kit, transmission line fitting kit, and oil cooler install kit for Chevrolet Silverado 1500, GMC Sierra 1500, and Cadillac Escalade applications.

Vehicle coverage includes many Chevrolet Silverado 1500, Tahoe, Avalanche, Colorado, Express, and Suburban models; GMC Sierra, Savana, and Yukon applications; plus Cadillac CTS, Escalade, DTS, and DeVille listings. The Hayden 390 part number is also referenced in interchange listings for related service applications.

Common Uses

• Replacing worn or damaged transmission cooler line fittings
• Restoring a secure connection at the transmission oil cooler line
• Addressing leaks at inverted flare or snap-in style line connections
• Servicing transmission cooling lines during repair or replacement work
• Correcting fitment issues on vehicles using a matching cooler line connector kit

Installation Notes

Verify the vehicle’s transmission line style before installation. This kit is listed for applications using 5/8"-18 thread inverted flare fittings and snap-in type transmission line fittings, depending on the vehicle. Gaskets and seals are not included, so reuse or replacement of sealing components must be handled separately where required. Confirm connector orientation, thread style, and line routing before tightening the fittings.

Quality Assurance

Hayden 390 is a performance-rated steel fitting kit built for transmission cooling service. It is cataloged as a direct service part for the listed applications and is identified by the Hayden part number 390.