Transmission Air Pressure Test
WARNING: This page is about a different variant/trim than selected.
| Item | Description |
|---|---|
| 1 | Foward clutch |
| 2 | Direct clutch |
| 3 | Intermediate clutch |
| 4 | Low reverse clutch |
| 5 | Overdrive clutch |
NOTE:
The transmission end cover contains an air bleed for the intermediate clutch circuit. Some leakage during the air test can be normal.
NOTE:
The Low reverse piston contains an air bleed for the Low reverse 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.
- 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. Hydraulic circuits that use scarf cut seals and/or air bleeds will have some normal leakage.
- 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.
NOTE:
Use a rubber block with a hole drilled in it to seal the clutch ports.