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HOMESERVICE MANUALSGMC1998CAB & CHASSIS C2500, 5.7 KREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 617 (AUTOMATIC TRANSAXLE, 4T65-E DIAGNOSTICS (TROUBLESHOOTING))TROUBLESHOOTINGINCORRECT LINE PRESSURE
1998 GMC Cab & Chassis C2500, 5.7 K

Incorrect Line Pressure

1998 GMC Cab & Chassis C2500, 5.7 KSECTION Incorrect Line Pressure
WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
Incorrect Line Pressure

Checks Cause
DEFINITION: Transmission main line pressure that is determined to be high or low. Refer to Line Pressure Check Procedure .
Automatic Transmission Fluid Level - low pressure only Low fluid level
Thermo Element Assembly - low pressure only
  • The thermo element plate pins (120, 123) are misadjusted.
  • The thermo element (121) or the thermo element plate (122) is out of position, missing, or damaged - causing low fluid level in the oil pan.
Oil Filter and Seal Assembly
  • The oil filter assembly (100) is missing or damaged.
  • The oil filter seal assembly (101) is missing or damaged, low pressure only.
Wiring Harness Assembly The wiring harness assembly (224) is disconnected or damaged.
Oil Pump Assembly
  • The following components are worn or damaged - low pressure only:
    • The oil pump cover (201)
    • The oil pump body (202)
    • The oil pump vane ring (209)
    • The oil pump rotor (210)
    • The oil pump vanes (211)
    • The oil pump slide oil seal ring (212)
    • The oil pump slide O-ring seal (213)
    • The oil pump slide (214)
  • The oil pump slide (214) is binding, high pressure only.
  • The oil pump prime springs (222, 223) or the oil pump slide pivot pin (215) is missing or damaged, low pressure only.
  • The oil pump slide seal (220) or the oil pump slide seal support (221) is missing or damaged, high pressure only.
Pressure Control Solenoid Valve Assembly
  • The pressure control solenoid valve assembly (322) is damaged.
  • The solenoid valve O-ring seals (305, 316) are missing or damaged.
  • The valve retainer (314) is missing or damaged.
Torque Signal Regulator Valve Assembly
  • The torque signal regulator valve (321) is binding or damaged.
  • The valve retainer (314) is missing or damaged.
Pressure Regulator Valve Assembly
  • The pressure regulator valve (313) is binding or is damaged.
  • The pressure regulator valve springs (311, 312) is missing or damaged.
  • The reverse boost valve (310) is binding or is damaged, high pressure only.
  • The line boost valve (304) is binding or is damaged, high pressure only.
  • The valve retainer (302) is missing or is damaged.
Actuator Feed Limit Valve Assembly - low pressure only
  • The actuator feed limit valve (414) is binding or is damaged.
  • The actuator feed limit valve spring (415) is missing or is damaged.
  • The actuator feed limit valve spring retainer (416) is missing or damaged.
Low Blow Off Valve Assembly - low pressure only
  • The low blow off valve spring (323) is missing or is damaged.
  • The low blow off ball valve (324) is missing, binding, or is damaged.
  • The low blow off valve spring retainer (325) is missing or is damaged.
RENDER: 1.0x

NO RELATED

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