A/T Fluid Cooler Diagnosis Procedure

WARNING: This page is about a different car, the 2019 Nissan NV3500 HD, 2019 Nissan NV2500 HD, and 2019 Nissan NV1500. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Insufficient cleaning of the cooler inlet hose exterior may lead to inaccurate debris identification.

Position a drain pan under the A/T inlet and outlet fluid cooler tube to cooler hose connection.
Clean the exterior and tip of the cooler inlet hose.
Put a different color matching mark on each cooler tube to cooler hose connection to aid in assembly.
CAUTION: Use paint to make the matching mark. Do not damage the tubes or hose.
Disconnect the fluid cooler inlet and outlet rubber hoses from the steel cooler tubes.

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NOTE: Replace the cooler hoses if rubber material from the hose remains on the tube fitting.
Insert the extension adapter hose of a can of Transmission Cooler Cleaner into the cooler outlet hose.

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CAUTION:
- Wear safety glasses and rubber gloves when spraying the Transmission Cooler Cleaner.
- Spray cooler cleaner only with adequate ventilation.
- Avoid contact with eyes and skin.
- Do not breath vapors or spray mist.
Hold the hose and can as high as possible and spray Transmission Cooler Cleaner in a continuous stream into the cooler outlet hose until fluid flows out of the cooler inlet hose for 5 seconds.
Tie a common white, basket-type coffee filter to the end of the cooler inlet hose.

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Insert the tip of an air gun into the end of the cooler outlet hose.

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Wrap a shop rag around the air gun tip and end of cooler outlet hose.
Blow compressed air regulated to 490 - 883 kPa (5 - 9 kg/cm ² , 71 - 128 psi) through the cooler outlet hose to force any remaining A/T fluid into the coffee filter.
Remove the coffee filter from the end of the cooler inlet hose.
Perform A/T fluid cooler inspection.