Koyo XC251108W Universal 25 Row Aluminum Oil Cooler 11.25x7.5 50mm -10 AN ORB

Vehicle Fitment

• Universal - Not vehicle-specific. Suitable for any application where an external oil cooler can be plumbed using -10 AN ORB fittings, including engine oil, transmission fluid, differential fluid, and power steering fluid cooling circuits.

Fitment Notes

• This is a universal oil cooler core. A sandwich plate adapter, AN fittings, and hose or line routing are required for installation - none of these components are included.
• Inlet and outlet provisions are -10 AN ORB (O-Ring Boss). Adapters are required to connect to AN lines, Push-Loc barb fittings, or vehicle-specific oil filter sandwich plates.
• Sandwich plate adapter thread reference (verify with factory service manual before purchasing): 20mm x 1.5 thread for Acura (all), Honda (all), Mazda (all), Mitsubishi Turbo 4-cylinder. 3/4-16 UNF thread for BMW (all with spin-on filters), Nissan S13 SR20DET, Nissan RB26DET, Toyota (all), Scion (all), Mitsubishi Non-Turbo 4-cylinder.
• Professional installation is strongly recommended due to the custom plumbing required.

Features

• 25-row all-aluminum construction with a 50mm core - designed to deliver maximum heat rejection within a compact, lightweight package suitable for tight engine bay installations.
• Proven race-developed design: Koyorad custom oil coolers have competed in D1 Grand Prix and D1 Street Legal competition in Japan on factory-sponsored vehicles, where they must withstand indirect airflow, vehicle contact, and sustained high oil pressures.
• Versatile -10 AN ORB (O-Ring Boss) inlet and outlet provisions allow the cooler to be configured with AN-to-AN reducers or AN-to-Push-Loc barb fittings to accommodate a wide range of installation budgets and line routing requirements.
• Pressure tested to 10 Bar (145 PSI) burst resistance and deformation tested to 35 Bar - certified to handle the sustained oil pressures generated by high-performance and racing engines.
• Suitable for cooling engine oil, transmission fluid, differential fluid, and power steering fluid - making it a versatile choice for a wide range of cooling circuit applications.
• Optimized internal flow geometry ensures first-class cooling efficiency regardless of operating conditions, including low-airflow environments common in drift and circuit racing.
• Approximately 0.6L (~1 quart) fluid capacity - meaningful reserve volume that contributes to overall oil temperature stability under sustained high-load driving.
• Same level of precision engineering and manufacturing attention to detail as Koyorad's full racing radiator lineup - built to ISO 9001-certified standards in Japan.

Specifications

• Part Number: XC251108W
• Rows: 25
• Core Length: 11.25" (286mm)
• Core Height: 7.5" (191mm)
• Core Width / Thickness: 2.0" (50mm)
• Fluid Capacity: Approximately 0.6L (~1 quart)
• Inlet/Outlet Fitting: -10 AN ORB (O-Ring Boss) provisions - both inlet and outlet
• Fitting Compatibility: Adaptable to AN-to-AN fittings or AN-to-Push-Loc barb fittings (adapters sold separately)
• Pressure Rating: 10 Bar / 145 PSI (burst resistant)
• Deformation Rating: 35 Bar
• Material: Full aluminum construction
• Application: Universal - engine oil, transmission, differential, power steering
• Origin: Manufactured in Japan

Included Components

• 1x Koyo XC251108W 25-Row Universal Oil Cooler Core

Product Description

The Koyo XC251108W is a 25-row universal all-aluminum oil cooler core developed by Koyorad for performance and racing applications requiring an external fluid cooling solution. Measuring 11.25" x 7.5" with a 50mm thick core, it carries approximately 0.6 liters of fluid capacity and is designed to cool engine oil, transmission fluid, differential fluid, or power steering fluid - giving builders the flexibility to deploy it wherever thermal management is needed most. The design was born from Koyorad's factory racing program in Japan, where their oil coolers compete in D1 Grand Prix and D1 Street Legal events on purpose-built drift cars subjected to inconsistent airflow, contact loads, and sustained high oil pressures. The XC251108W brings those competition-proven engineering standards to a universal platform available to any builder.

Both the inlet and outlet are -10 AN ORB (O-Ring Boss) provisions, which offer broad compatibility with the most common performance plumbing systems. Users can connect the cooler directly to -10 AN hard or braided lines, or reduce to smaller AN sizes, or convert to Push-Loc style barb fittings depending on the installation. A vehicle-specific oil filter sandwich plate adapter is typically required to integrate the cooler into the engine's oil circuit - the correct thread pitch varies by manufacturer (20mm x 1.5 for most Honda, Acura, Mazda, and Mitsubishi Turbo applications; 3/4-16 UNF for most Toyota, BMW, and Nissan RB/SR applications - always verify with the factory service manual). Hoses, fittings, and sandwich adapters are not included and must be sourced separately.

The XC251108W is pressure tested to 10 Bar (145 PSI) and deformation tested to 35 Bar, confirming its structural integrity under the sustained high oil pressures generated by turbocharged, supercharged, and high-revving naturally aspirated engines. Every unit is built at Koyorad's ISO 9001-certified facilities in Japan to the same exacting manufacturing standards applied to their full racing radiator lineup. Whether used as part of a comprehensive cooling system upgrade alongside a Koyorad racing radiator, or as a standalone solution for a specific fluid circuit, the XC251108W delivers race-proven thermal performance in a compact, lightweight, and versatile package.