Final Drive, Differential - 0B5A (S-Tronic) Transmission

Left Flange Shaft Ball Bearing Pre-Tension, Checking

=> [ Pre-Tension on Ball Bearing, Optimizing, Left Flange Shaft ]

=> [ Pre-Tension on Ball Bearing, Adjusting, Left Flange Shaft ]

Check the Ball Bearing Pre-Tension using the Wear Pattern on the Bearing Bracket - arrow -.






• The pre-tension on the left flange shaft ball bearing must be checked only on certain vehicles. Refer to the table for a list of the vehicles => [ Vehicle Model ] Left Flange Shaft.

• This is not necessary on vehicles built later because they have been redesigned.

• Left flange shaft removed, refer to => [ Left Flange Shaft ] Left Flange Shaft.

Wear pattern"A"






• Small indentations near the hole on the bearing bracket - arrows -.

• No trace of wear or material erosion.

- Optimize the pre-tension on the ball bearing for the left flange shaft.

Wear Pattern "B"






• Traces of wear, if necessary, with material erosion all around the hole on the bearing bracket - arrow -.

- Adjust the pre-tension on the left flange shaft bearing.

- Replace the bearing bracket, the ball bearing and the circlip. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket.

Pre-Tension on Ball Bearing, Optimizing, Left Flange Shaft

• The pre-tension on the left flange shaft ball bearing must be optimized only on certain vehicles. Refer to the table for a list of the vehicles => [ Vehicle Model ] Left Flange Shaft.

• This is not necessary on vehicles built later because they have been redesigned.

Procedure

• Left flange shaft removed, refer to => [ Left Flange Shaft ] Left Flange Shaft.

Conditions for optimizing:






• The bearing bracket does not show any traces of wear or material erosion.

• Small indentations near the hole on the bearing bracket - arrows - are permissible.

• Bearing bracket with wear pattern "A" (the bearing bracket does not show any traces of wear or material erosion).






• A shim is inserted into the bearing seat on the transmission to optimize the pre-tension on the ball bearing.

- Insert a shim (0B4 409 227) - 1 - into the bearing seat on the transmission before installing the flange shaft to improve the pre-tension.






- Install the left flange shaft. Refer to => [ Left Flange Shaft ] Left Flange Shaft.

Pre-Tension on Ball Bearing, Adjusting, Left Flange Shaft

Special tools, testers and auxiliary items required

• Straight Edge 500 mm (VAS 6075)

• The pre-tension on the left flange shaft ball bearing must be optimized only on certain vehicles. Refer to the table for a list of the vehicles => [ Vehicle Model ] Left Flange Shaft.

• This is not necessary on vehicles built later because they have been redesigned.

• Left flange shaft removed, refer to => [ Left Flange Shaft ] Left Flange Shaft.

• Bearing bracket with wear pattern "B" (traces of wear if necessary with material erosion all around the hole).






• The bearing bracket and ball bearing must be replaced. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket

Procedure






- Clean off any dirt and corrosion from the contact surface - arrow - using 150 grain sand paper.

• It is not necessary to sand the contact surfaces all the way down to bare metal. It is enough to just remove any dirt and corrosion.

- Clean the contact surface and bearing seat.

- Install the new left flange shaft ball bearing - arrow - into the bearing seat.






Next procedure:

• By bearing oversize (the bearing sticks out slightly above the contact surface)

• With bearing undersize (the bearing sits deeper than the contact surface).

Procedure if there is Bearing Oversize






- Place (VAS 6075) straight across the bearing and determine the distance to the contact surface on the transmission housing on both sides with the feeler gauge.

- Write down the measured value.

- Place the straight edge 90° offset across the bearing and determine the distance to the contact surface on the transmission housing on both sides with the feeler gauge.

- Write down the measured value.

Selecting Shim(s):

• Use the smallest value take from the four values to select the shim(s).

• Specified value, bearing oversize = 0.5 to 0.8 mm






Example

1 shim:

0.1 mm + 0.3 mm = 0.4 mm, "bearing pre-load is too small"

2 shims:

0.1 mm + 0.3 mm + 0.3 mm = 0.7 mm, "bearing pre-load is in the specified range"

• Result: Insert two 0.3 mm shims to reach the bearing pre-load = 0.7 mm within the 0.5 to 0.8 mm specified value.

Procedure if there is Bearing Undersize






• The bearing undersize can only be determined in the described procedure.

- Place (VAS 6075) straight across the contact surface on the transmission housing and measure the distance to the bearing on both sides with a feeler gauge.

- Write down the measured value.

- Place (VAS 6075) offset across the contact surface on the transmission housing and measure the distance to the bearing on both sides with a feeler gauge.

- Write down the measured value.

Selecting Shim(s):

• Use the largest value take from the four values to select the shim(s).

• Enter the measured bearing undersize as negative value ("-") into the calculation.

• Specified value, bearing oversize = 0.5 to 0.8 mm






Example:

1 shim:

-0.15 mm + 0.3 mm = 0.15 mm, "bearing pre-load is too small"

3 shims:

-0.15 mm + 0.3 mm + 0.3 mm + 0.3 mm = 0.75 mm, "bearing pre-load is in the specified range"

• Result: A 0.75 mm bearing pre-load within the specified value of 0.5 to 0.8 mm is reached by installing three 0.3 mm shims.

Continuation for All






- Replace the bearing bracket, the ball bearing and the circlip. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket.

- Insert the determined number of shims (0B4 409 227) - 1 - into the bearing seat on the transmission before installing the flange shaft.

- Install the left flange shaft. Refer to => [ Left Flange Shaft ] Left Flange Shaft.