Turning Torque
WARNING: This page is about a different car, the 2015 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Turning torque is performed as a two step process and is measured at the differential. The first step is to determine the proper shim selection for the differential. This will form the basis for all other measurements.
NOTE:
New tapered bearings must be installed to the differential and transfer shafts to ensure correct turning torque is obtained. The bearings can loose as much as one half of their turning torque after break-in. Lubricate the bearings with the recommended gear lube prior to their installation into the cases
NOTE:
Determine bearing pre-load for the differential first. Differential turning torque readings can be obtained only with the gear train removed from the case.
- Install new bearings to the differential and transfer gear shaft.
- Install a new differential bearing race into the bellhousing side of the transaxle case.
- Install a differential bearing that has been ground down on the outer edge for ease of insertion and the original shim to the gear side of the transaxle case.
- Install the differential assembly to the bell housing side of the case.
- Assemble the case halves and tighten the fasteners to 30 N.m (22 ft. lbs.) using a cross tightening sequence.
- Using (special tool #C-4995A, Tool, Differential Bearing Torque) (1) turn the differential 20-40 times in both directions to properly seat the new bearings.
- Using a beam or dial type torque wrench, check the turning torque of the differential assembly by rotating the differential both clockwise and counter clockwise. The turning torque should be 0.05-1.57 N.m (0.44 - 14 in. lbs.) If the result is not within specification, choose a 0.02mm (0.0008 inch) thinner or thicker shim.
- Install the chosen shim continuing to use the ground bearing.
- Re-assemble the case halves and recheck the turning torque. Repeat until the proper turning torque result is obtained.
- Install the correct shim and a new bearing.
- Install a transfer shaft race that has been ground down on the outer edge for ease of insertion and the original shim to the gear side of the transaxle case.
- Install the transfer shaft along with the differential into the case.
- Assemble the case halves and tighten the fasteners to 30 N.m (22 ft. lbs.) using a cross tightening sequence.
- Using (special tool #C-4995A, Tool, Differential Bearing Torque) (1) turn the differential 20-40 times in both directions to properly seat the new bearings.
- Using a beam or dial type torque wrench, check the turning torque of the differential assembly by rotating the differential both clockwise and counter clockwise. The turning torque should be 0.05-1.57 N.m (0.44 - 14 in. lbs.) If the result is not within specification, choose a 0.02mm (0.0008 inch) thinner or thicker shim.
- Install the chosen shim continuing to use the ground bearing race.
- Re-assemble the case halves and recheck the turning torque. Repeat until the proper turning torque result is obtained.
- Install the correct shim and a new bearing race.