Repair and Diagnosis (Single Page): Transmission: Clutches: Description

1987 Chevrolet Forward Control 4.8 T, Automatic, 400/M40SECTION Description

The mechanical clutch consists of a driven plate, pressure plate, a diaphragm-type spring, and a release bearing. The driven plate is splined onto transmission clutch shaft so that it can move back and forth when clutch is disengaged and turn the shaft when clutch is engaged.

The driven plate has friction pads riveted to both sides and has a flexible center with springs to absorb vibration. The pressure plate has a machined surface that fits against the driven plate and a diaphragm-type spring mounted in a cover on the pressure plate.

The spring holds the pressure plate and driven plate together against the flywheel when clutch is engaged. The release bearing rides on a sleeve that pushes in on center of diaphragm spring, releasing pressure on the pressure plate and driven plate to disengage clutch.

All vans have a pull rod from clutch pedal that moves a cross lever. All "P" series trucks have an upper pull rod from the clutch pedal to a bellcrank and a lower pull rod from bellcrank to lever to a cross lever. On all models, the cross lever moves clutch fork and the release bearing with an adjustable rod.

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