One very awesome thing I was able to get done at Tata Motors , sector 5 Noida is:
"Change of AMT Hydraulic Fluid"
No workshop anywhere wants to touch an AMT unit. Response is 'Sir, its too risky. If AMT goes kaput, it will cost you 3 Lakh'.
I knew what I was doing so I asked them to do it on my risk. Mechanic was good, I worked with him a bit and he understood what I was asking.
We used the small pipe and suction injection, and pulled most of fluid from reservoir (After removing the battery) and replaced the fluid. Repeated the process a few times. And managed to remove most of the bad 8 year old fluid and replaced equal quantity (+ 100ml extra).
After 2-3 hours of slowly doing this, he packed the car again.
With fingers crossed, I took the risk of starting the car and tried it. NO error codes, no locked gears etc. Came home carefully.
NOTE: also change the gear oil (Synthetic), usually good for 60-70K KM. But anyway changed it.
Its been 1 month. AMT response is much smooth now.
If you have a good mechanic, access to original Patronas AMT Fluid (Not gear oil), and know how to do it, I recommend changing AMT fluid after 5 years of 50K KM or 40K Gear Shifts.
Companies claim this fluid to be "Sealed for life", but it is not.