I just want to check if I have gathered correctly from what I read on this forum as to the GRX drivetrain. From what I read I understand that:
- There is no differential in the transfer case and so when four-wheel-drive is selected, the two propeller shafts are connected together in such a way that they are forced to rotate at exactly the same speed.
- Moving at speed on a straight road, assuming that the manual hubs are locked, four-wheel-drive high can be selected on-the-fly as the two propeller shafts will be moving at the same speed and can therefore be engaged on the move.
- One would not be able to engage four-wheel-drive high on-the-fly at speed if the manual hubs are not locked as that would imply that the front propeller shaft is stationary (the assumption is that the auto locking hubs have not come into operation).
- Engaging four-wheel-drive low requires a dead stop – at least in principle.
- Engaging rear differential lock requires a dead stop – at least in principle.
- When getting a very heavy load moving it should be possible in principle to shift from four-wheel-drive low to four-wheel-drive high or from two wheel drive low to two wheel drive high at low speed, provided care is used.