Chevrolet Silverado / GMC Sierra. Service manual — part 750

NO TORQUE CONVERTER CLUTCH RELEASE

NO REVERSE GEAR

FLUID PRESSURE HIGH OR LOW

Checks

Causes

Torque Converter Assembly (1) Diagnose torque converter for possible internal damage.
Fluid Pump Cover Assembly
(219)

Inspect for worn, damaged, or sticking converter feed
limit valve (220) and spring (221).

Inspect for worn, damaged, or sticking torque
converter clutch (TCC) control valve (227) and
spring (226).

Control Valve Lower Body
Assembly (307)

Inspect for worn, damaged, or sticking TCC regulator
apply valve (355).

Checks

Causes

Control Valve Upper Body
Assembly (304)

Inspect for worn, damaged, or sticking 3-5 reverse
regulator valve (336) and valve spring (326).

Inspect for damaged or missing #5 checkball.

Control Valve Lower Body
Assembly (307)

Inspect for worn, damaged, or sticking clutch select
solenoid valve 3 (352) and valve spring (353).

Checks

Causes

Torque Converter Housing with
Fluid Pump Assembly (2)

Inspect for worn, sticking, or damaged pressure
regulator valve (233).

Inspect for worn, sticking, or damaged pressure
regulator valve outer spring (234).

Inspect for worn, sticking, or damaged pressure
regulator valve inner spring (235).

Inspect for worn, sticking, or damaged isolator valve
(236) and sleeve (237).

Inspect for worn, sticking, or damaged pressure relief
ball valve (225).

Inspect for worn, sticking, or damaged pressure relief
ball valve spring (224).

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

ON-VEHICLE REPAIR INFORMATION

TRANSMISSION FLUID FILLER TUBE AND SEAL REPLACEMENT

REMOVAL PROCEDURE

Inspect for damaged or porous pump cover assembly
(219). Inspect for pump surfaces not flat.

Inspect for excessive fluid pump rotor (217)
clearance or damage. Ensure proper selective rotor is
being utilized.

Inspect for damaged fluid pump slide (212). Ensure
proper selective slide is being utilized.

Inspect for worn, sticking, or damaged fluid pump
slide outer spring (211).

Inspect for worn or damaged fluid pump slide seal
(213), seal support (214), pivot pin (215), fluid seal
ring (209), and O-ring seal (210).

Inspect for worn or damaged fluid pump vane rings
(207) and rotor guide (208).

Control Valve Upper Body
Assembly (321)

Inspect for worn, sticking, or damaged actuator feed
limit valve (325) and spring (324).

Inspect for worn, sticking, or damaged clutch boost
valve (329) and spring (330).

Fluid Filter Assembly (26)

Inspect for damaged or restricted fluid filter assembly
(26).

Inspect for damaged fluid filter seal assembly (25).

NOTE:

Data below covers ON-VEHICLE repair information. For off vehicle
repair information see OFF-VEHICLE REPAIR INFORMATION.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Fig. 25: View Of Transmission Oil Level Indicator
Courtesy of GENERAL MOTORS CORP.

1. Unlock the transmission oil level indicator.

2. Remove the transmission oil level indicator.

3. Remove the transmission. Refer to Transmission Replacement.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Fig. 26: View Of Oil Level Indicator Tube & Transmission Seal
Courtesy of GENERAL MOTORS CORP.

4. Remove the oil level indicator tube (1).

5. Remove the seal (2) from the transmission.

INSTALLATION PROCEDURE

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - 6L50/6L80/6L90 - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado