On-Bench Torque Bias Tests

On-Bench Tarque Bias Test

NOTE: The following procedure can be used as both a diagnostic procedure and a means of verifying the coupling operation prior to assembly and installation of the transfer case.

Remove and disassemble the transfer case. Install the clutch gear on the side gear.

Install the assembled clutch gear and side gear in the viscous coupling (1).

CAUTION: Wooden blocks must be placed between the vise jaws and side gear to avoid damaging the gear.

Mount the assembled coupling and gears in a vise. Place wooden blocks (2) between the vise jaws and side gear and clamp the side gear firmly.

Check for engagement of the clutch gear in the viscous coupling. Ensure the gear is fully engaged in the coupling before proceeding. If necessary, loosen the vise and reposition the wooden blocks so they support the gear in the coupling.

Install the rear output shaft in the viscous coupling.

Install the yoke (3) on the rear output shaft (4) and install the retaining nut.

Assemble and position a socket and torque wrench (5) on the yoke retaining nut.

Rotate the rear output shaft using the torque wrench and note the torque required to rotate the shaft in the coupling.

The torque required to rotate the shaft in the coupling should be a minimum of 34 Nm (25 ft-lbs).

If the required rotating torque is less than specified, the coupling has malfunctioned. If the required torque is at or above the specified value, the coupling is in good condition.