33 12 551 - Drive pinion and ring gear, replacing < 33 - Rear Axle < BMW 728 - 745i
 
From model '83
REPLACING DRIVE PINION AND
RING REAR

(FINAL DRIVE REMOVED)

Remove drive pinion (see "Replacing Shaft Seal
and Input Flange" - 33 11 011).
Important!
Measure total friction torque and note value.
Mark bearing caps.
Don´t mix up washers.
Measure friction torque of drive pinion bearings
and note value.


Siehe auch 33 11 011
2033009 - click to zoom
 
Pull out front bearing outer race with Special
Tool 33 1 350.
1 Spreader
2 Front bearing outer race
3 Pulling bell
4 Pressure bolt

2833012 - click to zoom
 
Pull out rear bearing outer race with Special
Tool 33 1 360.
Puller consists of:
Puller head 33 1 351
Threaded spindle 33 1 362
Bearing bridge 33 1 356
Pressure nut 33 1 363
Important!
Shim (X) is located underneath the rear bearing
outer race and will be required again for adjustment
of drive pinion.

2833013 - click to zoom
 
Install old shim (x) in front of rear bearing
outer race.
Pull in bearing outer races with Special Tool
33 1 360.
Puller consists of :
Pulling disc for front race 33 1 373
Pulling disc for rear race 33 1 365
Threaded spindle 33 1 362
Pressure nut 33 1 363
Nut 33 1 354

2833014 - click to zoom
 
Press taper roller bearing on to drive pinion with
Special Tool 33 1 020.

2833015 - click to zoom
 
Important!
Drive pinions and ring gears are matched for
optimum smooth running in special machines.
The match code (P) is electrically inscribed in
the drive pinion and ring gear.
Never install a ring gear and drive pinion with
different match codes (P) together.

2833016 - click to zoom
 
The number inscribed with a + or - sign is the
deviation from basic setting C in hundredths of
millimeters and is required to determine thickness
of shim.
e + is added to C.
e - is subtracted from C.
K or H is tooth type code.
K = Klingelnberg teeth
H = Gleason teeth

2833017 - click to zoom
 
To determine the correct thickness of shim (X),
install drive pinion with new taper roller bearings,
but without the clamping bush.

2833018 - click to zoom
 
Place drive pinion in rear bearing outer race.
Screw Special Tool 33 1 341 on drive pinion
and pull front taper roller bearing on to drive
pinion with Special Tools 23 1 300 and
33 1 342.

2033017 - click to zoom
 
Attach drive flange.
Tighten collar nut to adjust friction torque of
drive pinion taper roller bearing to 250 Ncm
(22 in. Ibs.).

2033072 - click to zoom
 
Mount dial gauge in Special Tool 33 1 461.
Place Special Tool 33 1 461 with dial gauge on
Special Tool 33 1 462 and set dial gauge with
preload to 0 (zero).

2833019 - click to zoom
 
Place Special Tool 33 1 462 on drive pinion.
Place Special Tool 33 1 461 in case.
Determine Y.
Basic setting C = 11.50 mm (0.453")
Master gauge B = 9,50 mm (0.374")

2833043 - click to zoom
 
Example I
C 11.50 mm (0.453")
e - 0.10 mm (0.004")
--------------------------------------------------------------
C target 11.40 mm (0.441")
Value Y measured
with dial gauge 1.80 mm (0.071")
Sum B 9.50 mm (0.374")
Sum Y + 1.80 mm (0.071")

----------------------------------------------------------------
C actual 11.30 mm (0.445")
-----------------------------------------------------------------
C target 11.40 mm (0.449")
C actual - 11.30 mm (0.445")
------------------------------------------------------------------
a 0.10 mm (0.004")
------------------------------------------------------------------
Master gauge A 4.14 mm (0.163")
- a 0.10 mm (0.004")
------------------------------------------------------------------
Shim X 4.04 mm (0.159")

If C target is greater than C actual,
" a" is subtracted (-) from shim thickness X.

The permissible tolerance for distance (X)
depends on the tolerance for a certain shim thickness
ranging from 0.01 to 0.03 mm (0.0004 to 0.0012").


 
Example II
C 11.50 mm (0.453")
e + 0.10 mm (0.004")
-----------------------------------------------------------
C target 11.60 mm (0.457")
Value Y measured
with dial gauge 2.20 mm (0.087")
Sum B 9.50 mm (0.374")
Sum Y + 2.20 mm (0.087")

------------------------------------------------------------

C actual 11.70 mm (0.461")
-------------------------------------------------------------
C actual 11.70 mm (0.461")
C target - 11.60 mm (0.457")
-------------------------------------------------------------
a 0.10 mm (0.004")
-------------------------------------------------------------
Master gauge A 4.10 mm (0.161")
+ a 0.10 mm (0.004")
--------------------------------------------------------------
Shim X 4.20 mm (0.165")


If C target is smaller than C actual,
" a" is added (+) to shim thickness X.

The permissible tolerance for distance (X)
depends on the tolerance for a certain shim thickness
ranging from 0.01 to 0.03 mm (0.0004 to 0.0012").

2833020 - click to zoom
 
Remove drive pinion and rear bearing outer race.
Press in shim (X) of determined thickness and
bearing outer race.
Install drive pinion with new clamping sleeve (2).
Knock in shaft seal and attach input flange.

2033016 - click to zoom
 
Tighten collar nut and measure friction torque.
Adjust drive pinion bearing to friction torque
value measured prior to disassembling plug 20
Ncm (2 in. IBS) for new shaft seal.

2833044 - click to zoom
 
Important!
Collar nut (1) must be tightened to at least the
specified torque value¹).
If this value is not reached or the friction torque
is exceeded, replace clamping bush (2) and
repeat check.


Siehe auch ¹) See Specifications
2033073 - click to zoom
 
Press pulse spider off of differential case.

2033011 - click to zoom
 
Installation:
Press on pulse spider with Special Tool 33 1 358.

2033012 - click to zoom
 
Detach ring gear (cold).
Installation:
Clean threads thoroughly with a tapper.
Heat ring gear to max. 100° C (212° F), checking
temperature with a thermocolor pencil.
Mount ring gear with 2 staybolts (made locally)
as guides.

2033024 - click to zoom
 
Install new bolts with Loctite No. 270 and
tighten in order of 1 through 10.
Tightening torque¹).
Tighten bolts to torque angle¹).


Siehe auch ¹) See Specifications
2033025 - click to zoom
 
Pull off taper roller bearing on differential case
with Special Tool 33 1 300.

2833067 - click to zoom
 
Installation:
Press on new taper roller bearing cold with
Special Tool 31 1 003.

2833022 - click to zoom
 
Lift out shaft seals from both bearing caps.
Installation:
Dip new shaft seals in final drive oil.
Knock in shaft seals against stop with Special
Tools 33 1 230 and 00 5 500.

2833023 - click to zoom
 
Press out bearing outer races with Special Tool
33 1 351.
Important!
Pulling spider must engage in bearing outer race.

2833024 - click to zoom
 
Installation:
Press in new bearing outer races with Special
Tool 33 1 365.

2833025 - click to zoom
 
Install bearing caps (marked) with corresponding
plates (1).
Check O-ring (2), replacing if necessary.

2033010 - click to zoom
 
Mount Special Tool 00 2 500 and measure backlash¹).
Important!
The tooth contact pattern is always deciding for
correctly adjusted drive pinion/ring gear sets.


Siehe auch ¹) See Specifications
2833026 - click to zoom
 
To check the tooth contact pattern, coat ring
gear with printer´s ink, turn ring gear several
times in both directions and stop suddenly with
a piece of hard wood.
Correct backlash and tooth contact pattern by
changing shims from one side to the other.

2833027 - click to zoom
 
Measure total friction torque and compare with
value determined prior to disassembling.
Add 20 Ncm (2 in. IBS) for replaced shaft seals
(each).

2033072 - click to zoom
 
Important!
Changing the total thickness of shims (1) would
change the friction torque value.
The backlash and tooth contact pattern must be
adjusted again after adjusting the friction torque.

2833029 - click to zoom
 
General Information on Tooth Contact
Pattern Adjustments

Gleason Teeth:
A
Correct tooth contact pattern without load.
A 1
Loads will shift tooth contact pattern outward
slightly.
Moving the gear ring will mainly change the
backlash, but will also displace the contact
pattern in axial direction of the teeth.
Moving the drive pinion will displace the contact
pattern in favor of tooth height, but the
backlash will be altered just very slightly.
Here are the four basically incorrect tooth
contact patterns, which usually appear in
combination.
Knowing these patterns will facilitate making
adjustments.

1. High, narrow contact pattern (tip contact)
on ring gear.
Move drive pinion toward ring gear shaft
and perhaps correct backlash by backing
ring gear off of drive pinion.
2. Deep, narrow contact pattern (root contact)
on ring gear.
Move drive pinion away from ring gear shaft
and perhaps correct backlash by moving in
ring gear.
3. Short contact pattern on small tooth end
(toe contact) of ring gear.
Move ring gear away from drive pinion.
Maybe move pinion closer to ring gear shaft.
4. Short contact pattern on large tooth end
(heel contact) of ring gear.
Move ring gear toward drive pinion.
Perhaps back drive pinion away from ring
gear shaft.

73033150 - click to zoom
 
Klingelnberg (Palloid) Teeth

Tooth contact pattern on forward and reverse
flanks of drive pinion should be at approximately
center of tooth length and tooth height.

B Tooth contact pattern off load.
C Tooth contact pattern under load.
D By install a thicker shim "X" behind drive
pinion the contact pattern of forward flank
will shift toward the large drive pinion diameter,
while on the small drive pinion diameter.
E Other possible changes.

73033117 - click to zoom