Operating - Transfer gearbox

Transfer gearbox

The second gearbox (known as the transfer gearbox) is used to select either the high or low gear range.

The low range should be used for all field work regardless of the wheels fitted.

High range should be used for road work only and allows a relatively high road speed to be used at relatively low engine revs.

The maximum road speed of 30mph (50kph) should never be exceeded - If you attempt to exceed this speed an audible warning buzzer will sound and the speed meter will flash. An engine cut-out will also come into effect just above the maximum permissible speed.

For some European countries the speed may be governed down to a lower speed and in some cases the transfer box may be locked into low range.

Changing range

The easiest way to change range is whilst moving very slowly on the road or a hard track.
Whilst slowing down to stop (below 4mph) release the accelerator, select 'N' and move the transfer lever quickly to the required high or low position. Reselect 'D' with the main gear selector and continue driving. After a little practice, this operation can be carried out smoothly and quickly by using firm, positive moves.

Differential lock

The transfer gearbox is fitted with a lockable centre differential. With the differential locked, the drive shafts to the front and rear axles are (in effect) joined together, causing both to rotate at the same speed. This feature enhances traction when working in difficult and slippery conditions and when working on steep hillsides. With the differential unlocked for normal conditions and roadwork, the different running requirements of the two axles can be accommodated, thereby enabling the Phantom to operate permanently in four wheel drive for both road and field work.

When to use the diff lock

As a general rule, the differential should only be locked on slippery or loose surfaces or on very steep hillsides. If any wheel slip is evident then it should, of course be used. However do not use it unnecessarily. It must be disengaged for all road work.

Selecting diff lock

The diff lock can be engaged or disengaged either with the vehicle stationary, or when driving along. However, with the vehicle in motion it is essential to be travelling on firm ground, in a straight line and without wheel slip.
Do not engage the diff lock if one or more wheels are slipping - this could result in serious transmission damage. If wheels are slipping, ease off the accelerator before engaging the diff lock.

Engaging diff lock - Move the lever backwards - the warning lamp will illuminate when the differential engages. NB The lamp will only light up when the lock is actually engaged - rather than when it has been selected. Similarly it will only extinguish when the diff is actually disengaged.
Dis-engaging diff lock - Move the lever forwards. If the warning light is obviously reluctant to extinguish after the diff lock has disengaged, some transmission 'windup' may be present. Reversing the vehicle for a short distance and then going forward will usually 'unwind' the transmission.

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