Yep most garages will not touch them here in the uk, I don't know why there's nothing complicated in them
They're not even hard (or particularly time consuming) to remove (apart from draining the coolant to get a bit more room, although I have done it without).
DIY rebuild is theoretically easy, but very hard to find seals at a sensible price. Done one (using mix of seals from 2 failed units) and it's still going. Got another 3 in the Round Tuit pile, waiting for me to find seals.
What I have found when messing about with Dualogics is that usually it seems to be one of 3 things that starts the problem, and it all goes wrong from there...
1. Accumulator failure. Owner keeps driving until motor starts blowing fuse or stops altogether.
2. Clutch worn out, owner keeps driving.
3. Gearbox input bearing & seal failure, owner keeps driving.
1 often leads to motor failure, or bad advice to "top it up" which often seems to go wrong on unexpected ways. Also bits of the accumulator membrane end up in the fluid and cause other problems.
2 seems to cause failure of the clutch actuator seal, sometimes followed by clutch replacement but no repair of the clutch actuator seal, leading to more problems.
3 stresses the seals in the change actuators, leading to leaks, as the gear shifting action is out of specification (i.e. too sloppy or too stiff, or expected movements do not result in selected gear)
I've always found the units to be very reliable unless abused, but I understand that others feel differently.
Willing to
donate a unit to someone who is serious about trying a rebuild, but ill be pointless unless you have access to a set of seals.
PS OEM accumulator is Magneti Marelli, as are other parts.