Australian Car Repair Issues? Ask an Auto Mechanic for Answers ASAP
Sounds like a transmission cooler hose has been damaged on assembly, or is now leaking since is has been disturbed.
You should get your mechanic out to your house for an inspection.
Do you need any further help?
I hope my advice has been of assistance to you.
Merry Christmas and a Happy New Year to you and your family.
That's great that your mechanic has fixed it for you.
Wishing you well for 2017.