GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Sierra - 4WD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 Symptom Diagnosis

Symptom Diagnosis (1999 GMT800 / 4L60-E)

Diagnostic Category

Diagnostic Information

This table consists of seven diagnostic categories that are located in the left-hand column. Using this column, choose the appropriate category based on the operating conditions of the vehicle or transmission. After selecting a category, use the right-hand column to locate the specific symptom diagnostic information.

Important: The Functional Test Procedure should be performed before beginning any diagnosis. If this procedure has not already been performed, refer to Functional Test .

Fluid Diagnosis

This category contains the following topics:

    • Fluid condition (appearance, contaminants, smell, overheating)
    • Line pressure (high or low)
    • Fluid leaks
    • Refer to Transmission Fluid Check .
    • Refer to Oil Pressure High or Low .
    • Refer to Fluid Leak Diagnosis (procedure).
    • Refer to Oil Out the Vent .
    • Refer to Front Oil Leak .

Noise and Vibration Diagnosis

This category contains the following topics:

    • Ratcheting noise
    • Noise (drive gear, final drive, whine, growl, rattle, buzz, popping)
    • Vibration
    • Refer to Ratcheting Noise .

Range Performance Diagnosis

This category contains the following topics:

    • Drives in Neutral
    • No Park
    • No Reverse
    • No Drive
    • No engine braking
    • Refer to Drives in Neutral .
    • Refer to No Park .
    • Refer to No Reverse or Slips in Reverse .
    • Refer to No Drive in All Ranges .
    • Refer to No Drive in Drive Range .
    • Refer to No Overrun Braking - Manual 3-2-1 .

Shift Quality (Feel) Diagnosis

This category contains the following topic:

    • Harsh, soft or slipping shifts
    • Harsh, soft or delayed engagement
    • Shift shudder, flare or tie-up
    • Refer to Harsh Shifts .
    • Refer to Slipping or Harsh 1-2 Shift .
    • Refer to Harsh Garage Shift .
    • Refer to Delay in Drive and Reverse .
    • Refer to 3-2 Flare or Tie-Up .

Shift Pattern

This category contains the following topics:

    • One forward gear only
    • Two forward gears only
    • Gear missing or slipping
    • No upshift or slipping upshift
    • No downshifts
    • Non-First gear start
    • Refer to First Gear Range Only - No Upshift .
    • Refer to Third Gear Only .
    • Refer to Slips in First Gear .
    • Refer to Slipping or Harsh 1-2 Shift .
    • Refer to Second Gear Start .

Shift Speed Diagnosis

This category contains the following topic:

Inaccurate or inconsistent shift points

Refer to Inaccurate Shift Points .

Torque Converter Diagnosis

This category contains the following topics:

    • Torque converter diagnosis
    • TCC does not apply
    • TCC does not release
    • TCC apply/release quality
    • Refer to Torque Converter Diagnosis .
    • Refer to No Torque Converter Clutch Apply .
    • Refer to No Torque Converter Clutch Release .
    • Refer to Torque Converter Clutch Shudder .