Ford Fusion: Automatic Transmission - 6-Speed Automatic Transmission – 6F35 / Transmission Air Pressure Test. Diagnosis and Testing

Transmission Air Pressure Test

NOTE: The center support contains an air bleed for the forward and Low reverse clutch circuits. Some leakage during the air test can be normal.

NOTE: The Intermediate clutch pressure chamber contains an air bleed for the Intermediate clutch circuit. Some leakage during the air test can be normal.

A hydraulic clutch concern can be located through a series of checks by substituting air pressure for fluid pressure to determine the location of the concern.

1. Install the forward clutch and low/reverse clutch main control-to-transmission case seals.
   

1. Using a rubber tipped blow gun, apply 40 PSI (276 kpa) to the suspect clutch port for 2-3 seconds.
   
   • A dull thud indicates the clutch piston applied.
     
   • A hissing noise may indicate a leak in the hydraulic passages. Hydraulic circuits that use scarf cut seals and/or air bleeds will have some normal leakage.
     

1. While holding the blow gun nozzle firmly against the port in the transmission case, release the trigger.
   

1. Wait 1-2 seconds.
   
   • A hissing noise may indicate a leak in the hydraulic passages. Hydraulic circuits that use scarf cut seals and/or air bleeds will have some normal leakage.
     

1. Remove the blow gun from the port.
   
   • A sudden release of air pressure indicates the hydraulic passages are capable of holding pressure.
     
   • No noise may indicate a leak in the hydraulic passages. Hydraulic circuits that use scarf cut seals and/or air bleeds will have some normal leakage.