2002 2.2 Diesel Automatic

[YNOT]

I DONT KNOW IF ANYONE IS ABLE TO HELP, OR EVEN POINT ME IN THE DIRECTION OF SOMEONE WHO CAN........MY C5 DEISEL AUTOMATIC HAS A TENDENCY TO WANT TO CHANGE UP A GEAR OR DOWN, WHEN THE ENGINE REVS AND ENGINE SOUNDS SEEM TO SUGEST IT SHOULDNT......THE CHANGING IS JUST NOT CONSISTENT WITH THE REVS OR ROAD SPEED...PARTICULARLY WHEN RUNNING DOWNHILL, IT WILL CHANGE RIGHT DOWN WHEN THE ROAD SPEED AND NON LABOURING ENGINE SHOULD INDICATE IT REMAINS IN A HIGHER GEAR

[qman3428]

When did it last have the filters and oil in the gearbox changed? could be a simple fix.

[C5 PEH]

Changing down is normal when running down hill mine changes down as soon as i brake and then stays in that gear until you accelerate again needing more revs to change back up  than on the flat,this is great for saving the brakes as the engine is taking the strain  It is occasionaly odd but hey its french !!I would change the oil and filter  cant do any harm