Front suspension squeak on TD4

The front suspension on my TD4 (auto) squeaks loudly when going over slow bumps like speed humps. I have taken off the wishbones and greased them. The anti roll bar bushes have been replaced with poly ones but there is still this loud squeak. The vehicle is a 2002 so I am assuming it has the correct scrubbers in place on the wishbones.

Could this be an engine/gearbox mount issue?

Does anyone have any ideas?

Check the anti-roll bar drop links as well.

Get a silicon spray and squirt each joint in turn but check for squeaks in between, when the squeaking stops you have found your dodgy joint