I collected my car today after it was in for diagnosing excessive vibration and tranny noise after fitting the motor and tranny mounts. The tech said that all the mounts were fine and aligned properly so checked the tranny oil level; to which he stated "there wasn't any" he explained that it looked like someone had drained it and that there was about 1/4 litre left in it. I had the all common 6 speed bearing whine issue tended to about a year ago so I'm assuming it was topped back up after it was stripped. Surely they wouldn't have forgotten as I have done 9k miles since then and it would have seized??

There were no signs of leaks at all (hence him asking if it had been drained)

The tech topped it back up and said he added a treatment as he was unsure how long it had been low so gave it some extra protection. I am sceptical about the effect of these treatments over standard oil anyway but I went with it initially as he explained it well.

1. Can the transmission lose oil but not show signs of leaks?
2. Could the transmission last 9k without the gears touching any oil?
3. Do you think I've been suckered in to an oil fill and treatment sale to the total price of £27?

I'm struggling to feel any difference to be honest.
The vibration is still there (reduces at op temp)