L. Checking and If Necessary Adjusting Bearing Play

Dismantling and Assembling Transfer Case

L. Checking and If Necessary Adjusting Bearing Play

Preceding work:
Sun gear shaft removed (28-300, section A). A. Removal and Installation of Sun Gear Shaft
Center differential lock (ZS) pinton removed (28-300, section B). B. Removal and Installation of Center Differential Lock (ZS) Piston
Outer multi-disk carrier of front axle drive train (AV) removed (28-300, section C). C. Removal and Installation of Outer Multi-Disk Carrier of Front Axle Drive Train (AV)





Note: In order to ensure the satisfactory operation of the transfer case, the bearing preload is to be measured extremely carefully.

Unlock collar nut (49), 160 Nm and secure. Withdraw, slide on joint flange (19). Use Stud driver 129 569 01 07 00, socket wrench 126 589 02 09 00.

Dimension "X2" - Measure (X2 = 0.2 mm), adjust, if necessary remove to adjust bearing outer ring (50 b). Install shims (50e) (numbers 2 to 7).

Dimension "X1" - Measure (X1 = 0.2 mm), adjust, if necessary remove to adjust intermediate gear (17) and tapered roller bearing (17 b, 17 c), install shim (17a) (number 8).









Remove bearing outer rings (51a, 50c) from transfer case housing (28-300, section J).

Mount bearing outer rings (51a, 50c) on gear drives and output shaft (number 9).

Mount pressure members (53, 54, 55) on the bearing outer rings (51a, 50c) (number 10).

Mount retaining plate (52) and fasten to transfer case housing (number 11).

Tighten bolts (56, 57, 58) to 1 Nm (number 12).

Dimension "a" - Measure (number 13), enter in shop-made table.
Dimension "b" - Measure (number 14), enter in shop-made table.
Dimension "c" - Measure (number 15), enter in shop-made table.
Dimension "d" - Measure (number 16), enter in shop-made table.
Dimension "e" - Measure (number 17), enter in shop-made table
Dimension "f" - Measure (number 18), enter in shop-made table.

Calculate spacer thickness with aid of table and install.

Install bearing outer rings (51a, 50c) in transfer case housing (number 19).

Install 3-arm flange on front axle.

Measure output friction coefficient (number 20)

Special Tools:

Note: In order to ensure the satisfactory operation of the transfer case, the bearing preload is to be measured extremely carefully.


Measuring




1 Unlock collar nut (49) and slacken with socket wrench 126 559 02 09 00 whilst steadying with stud driver 129 559 01 07 00 and turn down. Withdraw joint flange (19).




2 Measure dimension "X2" between intermediate housing (26) and output shaft gear (18) with feeler gauge.
X2 = 0.2 mm (constant)

3 To adjust to the dimension "X2", remove bearing outer ring and insert suitable spacer.




4 Remove bearing outer rings (51a and 50c), output shaft (18), intermediate gear (17) and gear drive (8).




5 Drive out bearing outer ring (SOb) using suitable mandrel, install spacer (50e) depending on measured value.
Spacers are available in thicknesses of 0.05; 0.1; 0.3 and 0.5 mm.




6 Using mandrel (030) 201 589 00 15 00, press in bearing outer ring (50b) until it abuts.




7 Check dimension "X2"




8 Measure dimension "X1" between intermediate housing and intermediate gear (17) using feeler gauge. Insert spacer depending on the measured value.
X1 = 0.2 mm (constant)
Spacers are available in thicknesses of 0.05; 0.1; 0.3 and 0.5 mm.

9 Mount bearing outer rings (51a, 50c) on the gear drives and output shaft.

10 Mount pressure members (53, 54, 55) on the bearing outer rings (51a, 50c).

11 Mount retaining plate 124 589 23 21 00 and fasten to the transfer case housing.




12 Tighten bolts (56, 57, 58) to 1 Nm, centering the pressure member at the same time.
Note: The tightening torque of 1 Nm corresponds to a bearing pre-load of 0.05 mm.




13 Measure dimension "a" between the joint face of the transfer case housing and the bearing surface of the bearing outer ring and enter in shop-made table. Use Measuring bridge 126 589 04 31 00, magnet holder 116 589 12 21 00, dial gauge 001 589 82 21 00.




14 Measure dimension "b" between bearing outer ring and joint face of intermediate housing and enter in shop-made table. Use Magnet holder 116 589 12 21 00, Dial gauge 001 589 82 21 00.

Examples
Gear drive
Dimension "a" 51.42 mm
Dimension "- b" -51.11 mm
Difference 0.31 mm
Actual spacers installed 0.30 mm

Install or remove spacers with aid of table.
Note: When determining the thickness of the spacer, round off value downwards.




15 Measure dimension "c" between joint face of transfer case housing and bearing surface of bearing outer ring and enter in shop-made table. Use Measuring bridge 126 589 04 31 00, magnet holder 116 589 12 21 00, dial gauge 001 589 82 21 00.




16 Measure dimension "d" between bearing outer ring and joint face of intermediate housing and enter in shop-made table. Use Magnet holder 116 589 12 21 00, Dial gauge 001 589 82 21 00.

Output shaft
Dimension "c" 51.23 mm
Dimension "- d" -50.88 mm
Difference 0.35 mm
Actual spacers installed 0.35 mm

Install or remove spacers with aid of table.
Note: When determining the thickness of the spacer, round off value downwards.




17 Measure dimension "e" between joint face of transfer case housing and bearing surface of tapered roller bearing inner ring and enter in shop-made table. Use Measuring bridge 126 589 04 31 00, magnetic holder 116 589 12 21 00, dial gauge 001 589 82 21 00.




18 Measure dimension "f" between joint face of intermediate housing and bearing inner ring and enter in shop-made table. Use Magnet holder 116 589 12 21 00, Dial gauge 001 569 82 21 00.

Intermediate gear
Dimension "e" 37.69 mm
Dimension "- f" -37.17 mm
Difference 0.52 mm
Actual spacers installed 0.50 mm

Install or remove spacers with aid of table.
Note: When determining the thickness of the spacer, round off value downwards.

Checking the output torque

19 Install bearing outer rings of transfer case housing (28-300, section J). J. Removal and Installation of Bearing Outer Rings From Transfer Case Housing

20 Screw on 3-arm flange at front axle and measure output friction coefficient using a friction coefficient tester.
Specified value: 15 - 25 Nm
Note: If the output friction coefficient is excessive or insufficient, a mistake was made when measuring the bearing preload. In this case, repeat the complete measurement.