Power Transmission; Hitech Power Shuttle; Gearbox; Powershift - Valtra T151eLS Operator's Manual

In tractors with the power shuttle unit the traditional
forward/reverse gear lever is replaced with a shuttle lever
beside the steering wheel.
By moving the shuttle lever forwards or backwards (the
middle position is neutral) you get a gentle and light
shuttle operation without using the clutch pedal. Use of
the clutch pedal for shuttle operation is still possible.
The power shuttle is placed between the gearbox and the
Powershift. It has planetary---type gear drives which are
operated by two wet multi---disc clutches, one for forward
driving and one for reverse driving. Multi disc clutches
operate at the same time as the driving clutch due to this
the tractor not having a traditional dry clutch disc.
The function of the system is controlled by the electronic
control unit of the gearbox. This means that the
electronics smoothly adjust the disengaging and
engaging pressures of the hydraulic multi---discs
according to program. This provides smooth forward and
power shuttle driving.
In addition the system has the HiShift--- operation, with
switch placed in the gear lever, which controls the
operation of the multi---disc when changing gear. So it is
possible to change gear without using the clutch.
However, traditional use of clutch pedal is still possible.

Power transmission

C 4.

HiTech power shuttle

C 4.1.
The speed gearbox has four synchronized gears which
are controlled with a speed gear lever. Additionally
semi---automatic range gears, M=Medium range and H=
High range, are controlled with the horizontal movement
of the speed gear lever.
The LL=creeper range is controlled with one lever .
There is an EcoSpeed---function available on the tractors
(as alternative equipment). The EcoSpeed---function is
based on the 50 km/h transmission and the highest ratio
with the electric speed limiter (40 km/h). When driving at
road speeds the fuel consumption is lower and the noise
will be reduced.
In addition in front of the gearbox is a 3---step quick---shift
gear, the Powershift.
Control of the Powershift function is also controlled by the
electronic control unit, at which time the gearing is
selected according to the driving conditions.
Manual control of the Powershift--- gear is done with the
push button on the gear lever or with the push buttons on
the right---side arm rest. The driver can choose from the
---17---

Gearbox

C 4.2.

Powershift

C 4.3.
C. General description
T1LS C7