Line Pressure Check Procedure

Tools Required

• J 45542  Transmission Line Pressure Adapter
• SA9127E  Gage Bar Set

CAUTION: Keep the brakes applied at all times in order to prevent unexpected vehicle motion. Personal injury may result if the vehicle moves unexpectedly.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the left front splash shield. Refer to Splash Shield Replacement - Engine in Body Front End.
3. Remove the automatic transmission fluid pressure test hole plug (66) and O-ring seal (67).
Fig 1: View Of Automatic Transmission Fluid Pressure Test Hole Plug
Courtesy of GENERAL MOTORS CORP.
4. Install the J 45542  (2) with a sealing washer on each side of the adapter into the test hole.
5. Connect the SA9127E  (1) to the J 45542  (2).
Fig 2: Installing SA9127E & J 45542 To Transmission Test Hole
Courtesy of GENERAL MOTORS CORP.
6. Fully apply the parking brake.
7. Connect a scan tool for engine RPMs.
8. Start the engine and allow the engine to warm up at idle.
9. Firmly apply the brake and shift into REVERSE (R).
10. Allow the engine to idle and record the line pressure.

    Specifications:  500-610 kPa (73-89 psi)

IMPORTANT: Do not perform the 2600 RPM test longer than 5 seconds.
11. Increase the engine speed to 2600 RPM and record the line pressure.

    Specifications:  1710-1980 kPa (248-287 psi)

12. Allow the transmission fluid to cool at idle in PARK (P) for at least one minute.
13. Firmly apply the brake and shift into DRIVE (D).
14. Allow the engine to idle and record the line pressure.

    Specifications:  330-390 kPa (48-57 psi)

IMPORTANT: Do not perform the 2600 RPM test longer than 5 seconds.
15. Increase the engine speed to 2600 RPM and record the line pressure.

    Specifications:  1280-1418 kPa (186-206 psi)

16. If the line pressure reading is not within specifications refer to the Line Test Results table.
NOTE: Refer to Fastener Notice in Cautions and Notices.
17. Remove the tools and install the automatic transmission fluid pressure test hole plug (66) and a new O-ring (67).

    Tighten:  Tighten the test hole plug to 7 N.m (62 lb in).

Fig 3: View Of Automatic Transmission Fluid Pressure Test Hole Plug
Courtesy of GENERAL MOTORS CORP.
18. Install the left front splash shield. Refer to Splash Shield Replacement - Engine in Body Front End.