Oil Cooler & Fluid Coolers

Types of Transmission Cooler Lines and Oil Cooler Components

This category covers the components that route fluid between your cooler and your drivetrain, not the coolers themselves. Here's what you'll find:

• Transmission cooler lines and hose sets that carry fluid to and from the cooler
• Engine oil cooler hoses and tubes rated for high-temperature oil
• AN fittings, adapters, and swivel connectors for custom or replacement plumbing
• Mounting kits, brackets, and hardware that secure the cooler and lines
• Repair kits, retainer clips, and quick-connectors for factory-style lines

Filter by part type, brand, material, and outside diameter to narrow the list to parts that fit your car. Need the cooler itself? Shop the full oil and fluid coolers category, or browse transmission hoses, lines & fittings for drivetrain-specific plumbing. Add a vehicle to confirm fitment on application-specific parts, and check availability since many components ship the same day.

Transmission Cooler Lines and Hoses

Transmission cooler lines move automatic transmission fluid from the trans to the cooler and back, so they run under constant heat and pressure. Factory steel lines corrode, chafe, and split over time, which is why replacement lines, rubber hose sets, and repair kits are common fixes. You'll find pre-formed steel lines, flexible rubber hose, and braided assemblies built for higher-heat builds.

Choose a line rated for automatic transmission fluid, then match its outside diameter to your factory fittings. Steel lines resist abrasion and hold their shape, while rubber and braided hose flex around tight routing. Repair kits, retainer clips, and quick-connectors let you fix a factory line without replacing the whole assembly.

Check the position too, since inlet and outlet lines can differ in length and bend. For a shifter or trans upgrade, B&M transmission parts pair well with fresh cooling lines. Our hose guide for transmission cooler lines walks through the right material for the job.

Engine Oil Cooler Lines, Hoses, and Mounting Kits

Engine oil cooler lines and hoses carry hot oil to a remote or stacked-plate cooler, then return it to the block or filter housing. They're built for higher temperatures than transmission lines, so material, wall rating, and routing all matter. You'll find pressure and return hoses, oil cooler tubes, and complete hose assemblies for common engines.

Match each hose by its outside diameter and grade so it seals against the fitting and handles the heat. Route lines away from headers and moving parts, and leave slack for engine movement. Replace any oil line that hardens, cracks, or weeps at the ends.

Mounting kits, brackets, and sandwich adapters position the cooler for clean airflow without stressing the hose. A sandwich adapter taps oil at the filter, so you can add a cooler without cutting factory lines.

Mishimoto oil cooler kits come with matched lines and hardware. Our guide on which oil coolers are best for towing and daily driving helps you size the cooler.

AN Fittings, Adapters, and Connectors

AN fittings connect your lines to the cooler, pump, or block using a standardized sizing system. Most transmission and oil cooler plumbing uses -6AN or -8AN fittings, sized by the inside diameter of the hose. Aluminum swivel fittings let you set the angle after the hose is on, which makes final routing easier.

Straight, 45-degree, and 90-degree fittings route lines around tight engine bays without kinks. Swivel and quick-connect adapters simplify sealing and service, so you can break a connection without cutting the line. Match the AN size to your hose, and use thread adapters when the cooler and block use different port sizes.

Block-off plates cap unused ports on a sandwich adapter or cooler when you change the plumbing. Derale cooler fittings and components include adapters and block-off plates to finish a custom setup.

Choosing Hose Material and Size for Cooler Lines

Match hose material to the fluid and temperature it carries. Transmission cooler lines run cooler than engine oil lines, so a transmission-rated hose works for most trans setups. Oil lines see hotter fluid and need a higher heat rating.

Choose the construction that fits your build: rubber hose is affordable and flexible, braided stainless resists abrasion, and pre-formed steel holds a fixed shape. Size the hose by its inside diameter, then confirm the AN fitting or clamp matches. Add protective sleeving anywhere a line passes near a header or sharp edge.

Leave enough slack for engine movement so lines don't rub or kink, and replace any line that leaks, corrodes, or cracks. For sizing help, see how to choose the correct size transmission cooler. Flex-A-Lite coolers and fans pair with fresh lines.

Ready to finish the job? Shop cooling, heating & A/C parts for the rest of your cooling system.