Yes, you can normally drive without any vacuum lines connected to the
tranny diff lock actuator. There is a return spring inside the locker
that defaults to the unlocked position. You can verify the unlocked
status by raising both rear wheels and turning one forward by hand. The
other should spin backwards at the same time. With a working VC and
center shaft installed the wheel will only turn by hand with difficulty.
If it won't turn at all or turns freely, VC problems may be present.

Mark

Christopher Gronski wrote:

>Time is really working against me and I am not sure I will be able to
>remove all the plumbing for the differential lock of my donor van and
>transfer it over to my driver van. So my question is this:
>
>Can one drive a van with a differential lock without the plumbing? And
>how do I ensure the lock is not engaged?
>
>
>