Anyone know the amount of fluid needed on a service?

I know it is 1.5 litres on initial fill and then “fill to plug” on a service for the transfer box.
I have about 1.4 litres - is that enough?
I can always put a little of the old fluid back in if short…and if the old fluid looks same as new fluid going in ….

That isn't correct and you could end up blowing your transfer box. The diffs and transfer box are exact fill only, not to the plug.

I wrote a guide, which incorporates the relevant excerpts from the Land Rover workshop manual for the car here: https://www.fullfatrr.com/forum/topic67285.html 2015 Range Rover Autobiography 4.4 SDV8

The front and rear diffs must be filled with the correct quantity of oil as stated in post number 2 but the transfer box is filled to the level plug. Below is a direct quote from the workshop manual.

10. Refill transfer case with the recommended fluid, until the fluid is level with bottom of filler/level plug hole.

Its very important that the correct fluid is used. Be very nervous of claims that generic oils can be used.

Thanks Gents
I think we all agree it is to the fill plug
You both quoted from the manual - i had to dig through Gary’s post to find what he quoted:
“The workshop manual states to be level with the bottom of the fill hole.”

So any thoughts on volume?
How much remains from the original 1.5L fill in the box after draining ? 0.1L? 0.2L?

I will just pop a few mLs from the old oil back in if 1.4L is not enough

Yes maybe a slight difference in interpretation. The workshop specification says either a wet or dry fill is 1.5L, which should take the level to just below the fill plug, which is what the workshop procedure states.

I doubt less than 10% by volume of old fluid would do any harm, but if it were me, these don't get serviced regularly, so I'd buy an extra 500ml or 1L, to make sure anything put in is fresh fluid. 2015 Range Rover Autobiography 4.4 SDV8

I just checked with Andy from Glenrands.
They find that between 1.1L and 1.2L is the typical amount of Transfer box fluid they need for a service refill