Gearbox oil change - now puzzled

Hi all,

I'm now puzzled, i have just changed all the transmission oils on my RR P38. Diff's and trans box all ok and took the corrected amount of fluids but when i drained the gearbox only about 3 litres of transmission oil cam out. I then took the sump off and replaced the filter put everything back together. Filled it up without the engine running, then started her up and went through the gears. With the engine still running topped the oil off (as described in the manual) but it only took 4.5 litres to do this. Now the manual states 9.6 litres, and with putting a bit more in than what came out i feel ok about it but i was expecting to squirt in 9 litres.

Is this normal or have i done something wrong?

Cheers
Phil

You cant get it all out when you change it, so normally only a few Lt and its full, some leave it a few weeks and change it yet again, so as to get more fresh ATF in, but its working yea? then all is well and tickety boo as they say

Quite normal, takes less than five litres to fill.

cheers guys puts my mind at ease