Air Pressure Test
WARNING: This page is about a different car, the 2019 Ford F-350 Super Duty and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
| Item | Description |
|---|---|
| 1 | Intermediate clutch (C) port |
| 2 | Low/reverse clutch (D1) port |
| 3 | Not used |
| 4 | Direct clutch (B) port |
| 5 | Overdrive clutch (E) port |
| 6 | Forward clutch (A) port |
| 7 | Thermal bypass valve |
NOTE:
The center support contains an air bleed for the Low Reverse clutch. Some leakage during the air test can be normal.
NOTE:
Scarf cut seals require hydraulic flow to seal properly some leakage during air test can be normal. The direct clutch uses 2 scarf cut seals.
A clutch concern can be located by substituting air pressure for fluid pressure to determine the location of the concern.
- 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.
- While holding the blow gun nozzle firmly against the port in the transmission case, release the trigger.
- Wait 1-2 seconds.
- A hissing noise may indicate a leak in the hydraulic passages.
- 4. 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.