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Clutch Specifications
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Engine Model Year Damper
Clutch Disc Diameter Hub
V6, V8 1994-2001 4 11", 281mm  
V10, Diesel 1994-1999 5 12.3", 312.5mm 1.25"x12 spline
V10, ETC Diesel 2000-2002 9 12.3", 312.5mm

1.25"x12 spline

ETH (HO) Diesel 2001-2002 4 13.0", 330mm 1.375"x10 spline

The clutch mechanism:

The clutch mechanism consists of three main parts.
    A heavy plate flywheel is bolted to the rear of the crankshaft flange. The rear of the flywheel has a machined surface against which the clutch disk presses. A ring of holes is drilled and tapped into the rear flywheel face for attaching the pressure plate. Around the circumference of the flywheel is a ring gear which is engaged by the starter when the engine is cranked. Inertia of the rotating flywheel mass dampens the firing pulses of the engine and stabilizes the power flow to the drivetrain.
    A diaphragm type pressure plate is bolted to the flywheel. This pressure plate contains a one-piece spring and multiple release fingers. The finger adjustment is preset during assembly, and is not adjustable.
    A single dry-type disc is sandwiched between the flywheel and pressure plate. When the clutch is engaged, friction material riveted to the disc hub is clamped between the flywheel and pressure plate surfaces, transferring power from the engine to the transmission through splines in the disc hub.

Clutch operation:

    Pressure plate spring tension clamps the clutch disc against the flywheel to transfer power to the transmission. When the clutch pedal is depressed, a rod on the pedal presses a hydraulic master cylinder, which transfers fluid to a clutch slave cylinder causing it to extend against a clutch fork. The clutch fork levers against a release bearing, which presses the fingers on the pressure plate to release the clamping force and disengage the clutch.

Throwout bearing:

The throwout bearing is an angular contact, self centering design.

Repair Note: Many low-cost replacement bearings will fit, but they can not stand up to the pressure generated by hydraulically activated clutch used with the diesel engine.

Pilot bearing:

ETC Diesel & V10: 0.75" ID, 1.0" OD, 1" long.

Repair Note: According to Joe Donnelly, an oilite bonze bearing will extend the life of a worn input shaft nose.   South Bend Clutch (800-988-4543) has introduced a kevlar pilot bearing. A replacement input shaft is available from Standard Transmission.

Clutch slave cylinder rod travel:

If a customer complains of a soft pedal or a hard-to-shift concern, here are some diagnostic steps you can take. First, have someone actuate the clutch pedal while the technician checks the system for leaks. Next, check the fluid level in the master cylinder reservoir. If the fluid level is okay and there are no leaks to be found, try this little tip. Have someone push the clutch pedal to the floor and hold it while the technician measures the movement of the slave cylinder push rod. This can be done from the inspection hole in the dust cover using a small metal ruler. Then write down your measurement. The MINIMUM travel of the slave cylinder push rod needed to actuate the clutch properly is 23-24 MM.

Clutch slave cylinder replacement:

Dodge sells the master cyl/line/slave cyl as an expensive assembly.
NAPA United 360051 slave cylinder fits 1994-2001 5speed and 6 speed.
Some have reported that the NAPA part number is NCLCA61

1998 - 1999 Ram2500 with Cummins and 5-speed takes NAPA part #360085
Some have reported that the NAPA part number is NCLCA85
You can use the larger 360051 in 1998-2002 5 and 6 speeds, but you may have to ream the hydraulic fitting a little to get the 1/4" line to fit. The NAPA 360051 part is made by the same company as the Dodge one, but it's a much heavier duty piece with a larger cylinder for easier pedal effort!

The line is retained by a single rolled pin even though there are two holes are in the slave cylinder. The pin engages a shoulder on the line, and can be pushed out and reused.

To bleed it:
Fill the slave cylinder full with the piston expanded all the way out. Attach it to the line,and while holding the slave cylinder vertical (the line will flex enough) pump the piston back and forth so the bubbles float upward. It helps to have another person watching the fluid resivoir for bubbles. When the bubbles stop, you're done.


Last Update: March 5, 2000