The document provides instructions for improving installations of ZF 6-WG211 transmissions on Terberg tractors. The changes include using 3 flexplates instead of 2, adding a hardened center plate to the flywheel, reprogramming the transmission ECU, and checking and potentially replacing the converter, oil pump, and transmission components. The procedure involves removing the transmission, inspecting and replacing parts as needed, renaming the type shield, reinstalling the transmission, reprogramming the ECU, and returning the tractor to service. The instructions provide details on the specific steps for different engine models.

1. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 1/14
Service and Maintenance
Improvements on WG211 installation
Terberg YT / TT /RT **2 tractors
Scope of this instruction:
ZF introduced alterations in the ZF 6-WG211 transmission installation requirements.
The changes are: > A. The use of 3 instead of 2 flexplates.
> B. A hardened centre plate in the flywheel.
These changes have become standard for tractors produced from October 2007 of.
Practice shows that the 2 flexplate installation has a restricted lifetime. Since failures can
cause further damage to the installation Terberg and ZF decided for a full campaign. In line
with this campaign the following changes will also be implemented:
> C. Re-programming of transmission ECU
> D. Check of converter condition, replacement were required
> E. Check of oil pump condition, replacement were required
The procedure for this consist out 6 steps:
> 1. Removal of the transmission
> 2. Inspection
> 3. Rename type shield
> 4. Installation in the tractor
> 5. Re-Program of ECU
> 6. Return into service
As a guideline, this campaign repair takes 10 to 12 hours, depending if the oil pump needs to
be replaced. In some stages a help from a second man can be useful.
Document : Service.m30.doc SF362.02

2. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 2/14
Converter recognition
In this bulletin it is necessary to recognize the differences in converters used in the WG211
transmission. Below chart shows the dimensional differences as well as the numbers which
are stamped in the converter.
Transmission ‘long’ Converter ‘short’ Converter
4mm 2mm
ZF part ZF part
‘parts list No.’ Stamped no. Stamped no.
number number
4657 066 003
For 205kW engine: 21 0700 284 201 4168 034 077 21 0700 001 704 4168 034 124
Mercedes OM906LA
4657 066 004
For 170kW engine:
21 0700 284 203 4168 034 078 21 0700 001 706 4168 034 126
Mercedes OM906LA
Volvo TAD750VE
Document : Service.m30.doc SF362.02

3. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 3/14
1. Removal of the transmission
Before the transmission can be removed from the tractor following steps are required.
Remove the cover plates over the transmission.
Remove noise panels from underneath the transmission if they are installed.
For the ease of removal it is required to remove the dipstick from the transmission. To drain
the transmission oil quicker, you can partly loosen the dipstick tube.
The transmission contains approx. 21L of oil, so use an adequate sized, clean collecting
device. Depending on the condition of the oil, there can be decided to re-use it after
installation. Remove the dipstick completely.
Disconnect the oil lines to the oil cooler from the transmission.
Disconnect electrical wiring from the transmission. Make sure that you know were to connect
them to during installation, by marking the connectors were required.
Disconnect the prop shaft from the transmission. If required remove it completely by also
disconnecting it from the transfer case / rear axle.
On the back of the transmission a hydraulic pump is installed. Disconnect the pump, by
unscrewing it and tie it back as far away from the transmission as possible, leaving the hoses
connected.
Next the flexplates can be disconnected from the engine flywheel / adapter plate. The 4 bolts
can be taken out through the access cover plate, located in the flywheel housing bottom side
close to the engine sump.
Now the transmission is ready to be removed from the tractor, for which lifting is required.
Use, preferably, a suitable crane for this job.
A forklift truck can be used as alternative, but make sure that it has sufficient capacity and
that slings / belts / chains can not slide from the forks.
The transmission weight is approx. 500Kg, the converter has to stay with it, during removal.
Use proper lifting tackle and connect this to the lifting lugs on the transmission top.
Apply some tension with the lifting device.
On the RT type tractor it is required to remove the rear support from the transmission by
unscrewing it from the transmission. Be aware for the spring tension, doing this.
To completely remove the rear support, it is required to disconnecting the spring leafs from
the bracket.
Now the transmission mounting bolts, connecting the transmission to the engine flywheel
housing, can be removed. When removed, the transmission can be lifted out.
To do so, the transmission needs to be moved to the rear over approx. 80mm, so that
converter and converter spigot can clear the flywheel house.
Document : Service.m30.doc SF362.02

4. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 4/14
2. Inspection
> Converter re-use:
To determine if the ‘long ‘ converter can be re-used,
2 checks are required:
Check 1:
The horizontal distance from flexplate
mounting pads to converter spigot support
front face, which is nominal 4mm on the
existing converter, should not exceed 4,5mm.
If it does exceed, the converter needs
replacement.
Check 2:
Secondly the bearing behind the converter, which is part of the transmission oil pump,
needs to be inspected. To do so, the converter needs to be removed from the
transmission.
We advise to tilt the transmission slightly over the front, while removing the converter.
There is chance that the needle bearing cage is already damaged and that it drops out the
needles as soon as the converter is removed.
Tilting of the transmission can avoid that the needles fall in the transmission.
The bearing contains 56 needles.
Make sure that : > the transmission can not fall over.
> the converter doesn’t slide out the transmission by this manoeuvre.
If this bearing is damaged, the contact surface of the converter shaft inside the bearing can
also show wear. If this converter shaft is visually damaged, this is also a reason to replace
the converter.
To reinstall a converter, the transmission needs to be tilted, so that it rests on its back
( output shaft side down ). In this position all shafts are centred, so that the converter shaft
slides nicely over this.
Document : Service.m30.doc SF362.02

5. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 5/14
> Oil pump replacement required?
Since the bearing is an integral part of the oil pump, the oil pump needs to be replaced,
when the bearing needs replacement. For installing the oil pump, see the ZF instructions:
6WG211 - Conversion Instructions – Exchange transmissions Terberg.
> Transmission overhaul required?
If the transmission has been running for a longer period with a severe damaged bearing,
needles and metal debris will have entered the transmission. In this case the transmission
has to be revised by ZF. There are swing units available to replace the transmission.
Please contact Terberg Aftersales department to arrange for this replacement.
In case debris is found in the transmission oil cooler and oil lines, this needs to be cleaned.
Please consult Terberg Aftersales department for further instruction.
Document : Service.m30.doc SF362.02

6. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 6/14
3. Rename type shield
To be able to recognize the different transmission
installations after installation, the ‘parts list No.’ on
the type shield needs to be renamed as follows:
Original ‘parts list No.’ 3 flexplates + ‘long’ converter 3 flexplates + ‘short’ converter
4657.066.003 4657.066.020 4657.066.023
4657.066.004 4657.066.021 4657.066.024
Please stamp XX over the last numbers and stamp the last 2 digits of the new number
besides it in the type shield.
4. Installation in the tractor
On the engine side, the flywheel or flywheel adapter plate needs to be replaced. The new
installation gets an extra centre plate, which is hardened.
> Mercedes OM906LA
Remove the adapter plate t15012533. Install the adapter plate t15012761 with centre
plate t15012756, using screws t29020729. See figure 1 & 2.
> Volvo Penta TAD750VE
Remove the flywheel v20532339. Install the flywheel t15012762 with centre plate
v21112999. The old flywheel can be disposed. See figure 3 & 4.
Document : Service.m30.doc SF362.02

7. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 7/14
On the transmission WG211 side, 3 flexplates needs to be provided.
> Existing ‘long’ converter can be used:
Remove the 2 flexplates from the transmission. Install the new 3 flexplates pack to the
converter, using the supplied new bolts and the existing 2 washers. One washer located
under the bolt head and a washer between flexplates and converter.
Remove the transport bolts out of the clips, don’t loose the clips.
> With a new or existing ‘short’ converter:
Install a new 3 flexplates pack to the transmission with the supplied bolts.
Use in total 4x 1mm washers per screw. One washer located under the bolt head
and 3 washers between flexplates and converter.
Remove the transport bolts out of the clips, don’t loose the clips.
> When an overhauled transmission is installed:
In an overhauled transmission is a new converter used. Check if a 3 flexplates pack with
clips is installed. If not, then follow the instructions for a new converter.
Rename the type shield of the overhauled transmission according chapter 3.
When required adjustments on transmission and engine side are fulfilled, the transmission
can be re-installed to the tractor again.
Lift the transmission with the same precautions. Slide the converter spigot into the flywheel /
adapter plate centre ( provide some grease for this ). Pre-mount the bolts in the engine –
transmission connection. Install the bolts in the clips around the flexplates from underneath
engine. Install the transmission rear support, if this was removed.
Install the Hydraulic pump back in place. Connect the prop shafts.
Connect oil lines from the cooler, install the dipstick tube and reconnect electrics.
Torque all bolts to the required settings, see fig 5.
Fill the transmission again with the correct oil, as specified in the ZF recommendations or re-
use the oil which came out of the transmission. Make sure that the oil is clean.
Document : Service.m30.doc SF362.02

8. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 8/14
5. Re-Program of ECU
In line with this campaign, the transmission ECU needs to get a new program loaded.
For instructions read the modification bulletin 30-03/GB
6. Return into operation
If the transmission is installed, filled up with oil and the ECU is reprogrammed, the tractor can
be started and tested.
It is recommended to run an AEB calibration before the tractor is returned into operation.
For AEB-Calibration see procedure by the AEB-starter.
Check the oil level with running engine.
Make a test run, to check the operational performance of the transmission.
Finally check for any external oil leaks.
The tractor can be returned in operation.
Inform Terberg Aftersales department ( via involved service manager ) that a tractor has been
finalised. At least include following information:
> Tractor chassis number
> Running hours
> Repair date
> Status of old flexplates ( broken, cracked etc. )
> Is the converter and / or oil pump replaced?
> What number is stamped on the name shield
Document : Service.m30.doc SF362.02

9. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 9/14
Fig. 1
t29060266
t15012761
t15012756
t29020729
Engine: Mercedes OM906LA
Transmission: ‘long’ converter
Document : Service.m30.doc SF362.02

10. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 10/14
Fig. 2
t29060266
t15012761
t15012756
t29020729
Install additional
2
washers
Engine: Mercedes OM906LA
Transmission: ‘short’ converter
Document : Service.m30.doc SF362.02

11. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 11/14
Fig. 3
t29060894
t15012762
V21112999
V20405654
Engine: Volvo Penta TAD750VE
Transmission: ‘long’ converter
Document : Service.m30.doc SF362.02

12. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 12/14
Fig. 4
t29060894
t15012762
V21112999
V20405654
Install additional
2
washers
Engine: Volvo Penta TAD750VE
Transmission: ‘short’ converter
Document : Service.m30.doc SF362.02

13. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 13/14
Fig. 5
44 Nm + Loctite 243
83 Nm + Loctite 243
55-61 Nm
44 Nm
OM 906 LA
Engine side A
A
Section A-A
115 Nm + Loctite 262
Only by 'short' converter
ZF -WG 211
46 Nm
RT only 34 Nm
44 Nm + Loctite 243
Step 1: 20 - 30 Nm
Step 2: turn 60°
Step 3: turn 60°
55 - 61 Nm
TAD 750 VE
115 Nm + Loctite 262
Only by 'short' converter
ZF -WG 211
Non specified
tightening torques 46 Nm
according general
chart on next page RT only 34 Nm
Document : Service.m30.doc SF362.02

14. Modification Bulletin
Terberg Trucks
Date Group Nr. Pages
01-09-08 30 02/GB 14/14
Coarse metric threads
For assembly without grease For assembly with grease
Hexagon Flange Hexagon Flange
Tightening torque Tightening torque Tightening torque Tightening torque
Size Quality
(Nm) (Nm) (Nm) (Nm)
8.8 2,8 3,4 2,5 3,0
M4
10.9 4,1 4,7 3,7 4,3
x 0.7
12.9 4,8 5,5 4,3 4,9
8.8 5,5 6,6 4,9 5,9
M5
10.9 8,1 9,3 7,3 8,4
x 0.8
12.9 9,5 10,9 8,5 9,8
8.8 9,5 11,4 8,5 10,2
M6
10.9 14,0 16,1 12,5 14,4
x1
12.9 16,5 19,0 14,5 16,7
8.8 15,5 18,6 14 17
M7
10.9 23 26 21 24
x1
12.9 27 31 24 28
8.8 23 28 21 25
M8
10.9 34 39 30 35
x 1.25
12.9 40 46 35 40
8.8 46 55 41 49
M 10
10.9 68 78 60 69
x 1.5
12.9 79 91 71 82
8.8 79 95 71 85
M 12
10.9 117 135 104 120
x 1.75
12.9 135 155 121 139
8.8 125 150 113 136
M 14
10.9 185 213 165 190
x2
12.9 215 247 195 224
8.8 195 234 170 204
M 16
10.9 280 322 250 288
x2
12.9 330 380 300 345
8.8 280 336 245 294
M 18
10.9 390 449 350 403
x 2.5
12.9 460 529 410 472
8.8 390 468 350 420
M 20
10.9 560 644 490 564
x 2.5
12.9 650 748 580 667
8.8 530 636 470 564
M 22
10.9 750 863 670 771
x 2.5
12.9 880 1012 780 897
8.8 670 804 600 720
M 24
10.9 960 1104 850 978
x3
12.9 1120 1288 1000 1150
8.8 1000 1200 880 1056
M 27
10.9 1400 1610 1250 1438
x3
12.9 1650 1898 1450 1668
8.8 1350 1620 1190 1428
M 30
10.9 1900 2185 1700 1955
x 3.5
12.9 2250 2588 2000 2300
8.8 1850 2220 1600 1920
M 33
10.9 2600 2990 2300 2645
x 3.5
12.9 3000 3450 2700 3105
8.8 2350 2820 2100 2520
M 36
10.9 3300 3795 3000 3450
x4
12.9 3900 4485 3500 4025
8.8 3000 3600 2700 3240
M 39
10.9 4300 4945 3800 4370
x4
12.9 5100 5865 4500 5175
Source: VDI 2230, DIN 13 section 13, DIN 931, DIN 912
Document : Service.m30.doc SF362.02