The production process for oil coolers can vary depending on the type and specific application of the cooler, but here is a general overview of the process:

1. Design: design it according to the specific requirements and specifications of the application. Designers must consider factors such as the type of fluid being cooled, the temperature range, the flow rate, and the space available for installation.

2. Material selection: select the appropriate materials for the cooler, which may include aluminum, copper, brass, or stainless steel. 

3. Fabrication: The chosen material is then cut, shaped, and formed into the desired shape and size using specialized fabrication techniques such as stamping, forging, or welding. 

4. Assembly: The different components of the oil cooler are then assembled together, which may include fittings, hoses, and mounting brackets. 

5. Testing: test to ensure that it meets the necessary requirements and specifications.