Oil Cooler Flow Check

After the new or repaired transmission has been installed, fill to the proper level with DIAMOND ATF SP III or equivalent A/T fluid. The flow should be checked using the following procedure:

CAUTION: With the fluid set at the proper level, A/T fluid collection should not exceed one quart or internal damage to the transmission may occur.

Fig 1: Identifying Outlet Line (From Cooler)

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Disconnect the OUTLET line (from cooler) at the transmission and place a collecting container under the disconnected line.
Run the engine at curb idle speed with the shift selector in neutral.
If A/T fluid flow is intermittent or it takes more than 20 seconds to collect one quart of A/T fluid, replace the cooler.
If flow is within acceptable limits, reconnect the cooler line. Then fill the transmission to the proper level, using DIAMOND ATF SP III or equivalent A/T fluid.