When we refer to "cooler" we mean an oil cooler.
This is a small pipe that runs inside the side of the radiator. It has 2 openings (an in and an out) The cooler will look like 2 small metal openings on the radiator picture. Hot fluid enters the top opening and is cooled by conduction by the radiator and the cool fluid exits the bottom and returns to the source.
Example of an internal radiator transmission oil cooler:
Generally there are 2 types of oil coolers
Transmission Oil cooler = this cooler will accept your transmission oil and is on most automatic vehicles.
Engine oil cooler = this cooler will accept engine oil and is not on all radiators. this cooler is usually on the driver side of the radiator
When we mention "Radiator with 1 cooler" This means ONLY 1 side of the radiator will have a built in oil cooler. (2 connection points as pictured above)
When we mention "Radiator with 2 coolers" that means that BOTH sides of the radiators will have the additional openings indicating each side has a built in oil cooler. There will be then a total of 4 small connectors on the sides of the radiator. 2 on each side in addition to the inlet and outlet hoses
Easiest thing to do is look at the illustration online and compare between models. You'll see the difference if you look at the side area of the radiator.
RADIATOR WITH 1 COOLER:
- see the right side has the small connectors
- the left side only has the main plastic hose connection port
RADIATOR WITH 2 COOLERS
- See the left and right side have the small metal circles
Need More Help?