Transmission | 715.352 in model 956, 963, 964 |
with code G2B (Transmission G 211-12/14.93-1.0) | |
Transmission | 715.360 in model 963, 964 |
with code G2C (Transmission G 230-12/11.7-0.78) | |
Transmission | 715.371 in model 963, 964 |
with code G2E (Transmission G 281-12/14.93-1.0) | |
Transmission | 715.381 in model 963, 964 |
with code G2F (Transmission G 330-12/11.63-0.77) |
General
The Mercedes-Benz 12-speed transmissions with Mercedes PowerShift 3 have been optimized with regard to weight and oil charge. Reducing power loss was the main focus here. The surface of tooth flanks for constants (K1 and K2) of the splitter group was thus optimized with the superfinish manufacturing process so as to cause less dynamic friction.
A dog-type shift mechanism is installed in the range group instead of previous synchronization. This mainly decreases wear and reduces weight. In this context, the countershaft brake (12) was also developed further and optimized.
A new synthetic transmission oil (see Specifications for Operating Fluids) with lower viscosity also reduces the friction power in transmission. The transmission oil can be procured using the part number A 002 989 11 03 09, in 20-liter containers. At the same time, the oil fill capacity for certain vehicle model designations was reduced by 3 liters to 8 or approx. 11 liters. In this context, oil holes in transmission housing rear section (17) were changed and a new oil suction pipe (15) was installed in transmission housing center section (13, 14). The change intervals for transmission oil remain unchanged. The change intervals depend on the load and reach a maximum of 600,000 km
The optimized transmissions are installed as of 10/2016. The dog-type shift mechanism in the range group was already introduced for individual vehicle model designations in III/2016. The new transmissions cannot be differentiated from the previous transmissions based on major assembly model designations, codes or appearance. The transmissions can be identified by the actual value R 204 (range group with neutral position [yes]) in the transmission control unit (TCM). The reduced oil fill capacity is optional for new transmissions and can also be read out with the help of a transmission oil level control code (GO14) in VeDoc.
Dog-type shift mechanism in the range group
W26.10-1226-08
1 | Carrier ring | 5 | Synchronizer ring | |
2 | Synchronizer cone | A | Previous version | |
3 | Sliding sleeve with synchronizer body | B | Changed version | |
4 | Annular spring |
The synchronizer cone (2) and annular spring (4) were removed in the course of further development. A new special tool is currently being developed for removing the synchronizer body while disassembling the range group. The work instructions in the Workshop Information System (WIS) will be updated subsequently.
7 | Piston rod |
8 | Piston rod |
A | Previous version |
B | Changed version |
A | Notch |
W26.10-1227-05
The modified piston rod (8) now has an additional notch (A) for switching the center position of the range group.
W26.10-1228-08
10 | Sliding sleeve | A | Previous version | |
11 | Shift fork | B | Changed version |
The shift fork (11) with the sliding blocks was also modified and can only be installed with the modified sliding sleeve (10).
Countershaft brake (12)
W26.10-1231-08
12 | Countershaft brake | B | Changed version | |
A | Previous version |
With the introduction of constant-mesh range group, synchronization does not take place in the synchronizer cones anymore, but in the countershaft brake (12). The additional braking energy is dissipated through disks. In contrast to the previous procedure, the disks of the modified countershaft brake (12) no longer need to be oiled prior to installation.
The countershaft brakes (12) (housing, piston, disks or only the disks) of the previous version (A) can be replaced by the countershaft brake (12) of the modified version (B).
Reduction in oil fill capacity
W26.10-1229-08
13 | Transmission housing center section (G211-12 and G230-12) | n | Hole for low oil level | h | Hole for high oil level | ||
14 | Transmission housing center section (G281-12 and G330-12) |
13 | Transmission housing center section (G211-12 and G230-12) |
15 | Oil suction pipe |
16 | O-ring |
W26.10-1232-05
The design of transmission housing center sections (13, 14) and transmission housing rear sections (17) has been modified. The oil level could be lowered owing to a new oil suction pipe (15). The holes for filling oil have therefore changed slightly.
In case of a replacement part order for a new transmission housing center section (13, 14), oil suction pipe (15) is always delivered along with it.
The oil ducts to transmission housing rear section (17) for transmissions G211-12 and G230-12 were also optimized in conjunction with the introduction of oil suction pipe (15) in the transmission housing center sections (13, 14). For this reason, in case transmission housing center section (13) is replaced, the transmission housing rear section (17) must also be exchanged. Installing the complete "old" range group on the new transmission housing center section (13) is not possible (no oil ducts). On transmissions G281-12 and G330-12, the transmission housing center sections (14) can be exchanged without the transmission housing rear section (17).
17 | Rear section of transmission housing |
Pfeil | Oil ducts |
W26.10-1230-02
Oil ducts (arrow) were changed in transmission housing rear section (17).
18 | Oil distributor pipe |
A | Previous version |
B | Changed version |
W26.10-1233-05
In the optimized transmissions, a new oil distributor pipe (18) is used, which has two holes for each gear instead of one, for better oil distribution. The optional retarder is now also actively supplied with oil through an additional oil hole.
In case the oil distributor pipes (18) of the previous version (A) need repair, they are to be replaced by oil distributor pipes (18) of the modified version (B).