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6. Monitor transmission range on the scan tool, engine list. 1. Apply the brake pedal and ensure the parking brake is set. 2. Move the gear selector through all ranges. 3. Pause 2-3 seconds in each range. 4. Return gear selector to PARK. 5. Verify that all selector positions match the scan tool display. 7. Check throttle angle input. 1. Apply the brake pedal and ensure that the parking brake is set. 2. Ensure the gear selector is in PARK. 3. Monitor throttle angle while increasing and decreasing engine speed with the throttle pedal. The scan tool throttle angle should increase and decrease with engine speed. If any of the above checks do not perform properly, record the result for reference after UPSHIFT CONTROL AND TORQUE CONVERTER CLUTCH (TCC) APPLY The transmission control module (TCM) calculates the upshift points based primarily on 2 inputs: Perform the following steps: 1. Refer to Shift Speed and choose a throttle position shown to cover the normal driving range. 2. Monitor the following scan tool parameters: Throttle angle Vehicle speed Input speed - some models Engine speed Output shaft speed Commanded gear Cold transmission fluid-Check for low transmission fluid
2008 Chevrolet Silverado 1500 2008 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Slip speed Solenoid states 3. Place the gear selector in the OVERDRIVE position. 4. Accelerate the vehicle using the chosen throttle angle. Hold the throttle steady. 5. As the transmission upshifts, note the vehicle speed when the shift occurs for each gear change. There should be a noticeable shift feel or engine speed change within 1-2 seconds of 6. Compare the shift speeds to the Shift Speed table. Refer to Shift Speed . Shift speeds may vary slightly due to transmission fluid temperature or hydraulic delays in responding to Note any harsh, soft or delayed shifts or slipping. Note any noise or vibration. 7. Repeat steps 1-6 as necessary in order to evaluate the different throttle angles. 8. Check for TCC apply in THIRD and FOURTH gear. Note the TCC apply point. When the TCC applies there should be a noticeable drop in Check for DTCs. IMPORTANT: This transmission is equipped with an electronically controlled capacity clutch (ECCC). The pressure plate does IMPORTANT: The TCC will not engage until the engine is in closed loop operation and the vehicle speed is as shown in the Shift
2008 Chevrolet Silverado 1500 2008 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Refer to Torque Converter Diagnosis. Refer to the table Shift Speed for the correct apply speed. PART THROTTLE DETENT DOWNSHIFT 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to 64-88 km/h (40-55 mph) in FOURTH gear. 3. Quickly increase throttle angle to greater than 50 percent. 4. Verify the following: The TCC releases. The transmission downshifts immediately to THIRD gear. FULL THROTTLE DETENT DOWNSHIFT 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to speeds of 64-88 km/h (40-55 mph) in FOURTH gear. 3. Quickly increase throttle angle to 100 percent (WOT). 4. Verify the following: The TCC releases. The transmission downshifts immediately to SECOND gear. MANUAL DOWNSHIFTS The shift solenoid valves do not control the initial downshift for the 4-3 or the 3-2 manual Manual 4-3 Downshift 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to 64-88 km/h (40-55 mph) in FOURTH gear. 3. Release the throttle while moving the gear selector to THIRD. 4. Verify the following: The TCC releases. The transmission downshifts immediately to THIRD gear. The engine slows the vehicle.
2008 Chevrolet Silverado 1500 2008 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Manual 4-2 Downshift 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to 64-72 km/h (40-45 mph). 3. Release the throttle while moving the gear selector to SECOND. 4. Verify the following: The TCC releases. The transmission downshifts immediately to SECOND gear. The engine slows the vehicle. Manual 4-1 Downshift 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to 48 km/h (30 mph). 3. Release the throttle while moving the gear selector to FIRST. 4. Verify the following: The TCC releases. The transmission downshifts immediately to FIRST gear. The engine slows the vehicle. COASTING DOWNSHIFTS 1. Place the gear selector in the OVERDRIVE position. 2. Accelerate the vehicle to FOURTH gear with the TCC applied. 3. Release the throttle and lightly apply the brakes. 4. Verify the TCC releases. MANUAL GEAR RANGE SELECTION The shift solenoids control the upshifts in the manual gear ranges. Perform the following tests using 10-15 percent throttle angle. Reverse 1. With the vehicle stopped, move the gear selector to REVERSE. 2. Slowly accelerate the vehicle.
2008 Chevrolet Silverado 1500 2008 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E/4L70-E - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
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