The 6T70/75 transmission uses a pressure control system to apply and release clutchesduring shifts. The transmission control module (TCM) controls pressure commands tothe pressure control solenoids.
As normal wear of the transmission clutches occur, the TCM performs a clutch functionverification. The TCM momentarily commands a clutch on at a low pressure. The clutchfunction verification is conducted on smooth roads when the transmission is not shiftingand engine torque is consistent and positive.
When a clutch function verification is occurring, a slight bump or drag may be detectedmomentarily. The clutch function verification will occur a few times over severalminutes and will not repeat again for a thousand or more miles. This is a normalcondition and no repair attempts should be performed.
The clutch function verification will be performed sooner for a particular clutchif the TCM detects it is producing frequent poor shift control.
Transmission Adaptive Functions Automatic Transmission Unit
Transmission Adaptive Functions Automatic Transmission UnitFuel Injection Fuel Rail Assembly Replacement - Bank 1 Engine Control
Special Tools EN-49248 Injector Rail Assembly RemoverFor equivalent regional tools, refer toSpecial Tools.Removal ProcedureRelieve the fuel system pressure. Refer toFuel Pressure Relief.Remove the fuel pipe shield. Refer toFuel Pipe Shield Replacement.Remove the intake manifold. Refer toIntake Manif ...