E 320 model 1995 automatic gear problem
 

Had parked the car for a months time. Now when i drive it and put the "D" drive the car moves its gear fine, but if i want to downshift the gear by pressing the excelerator pedal even to its end the gears are not being downshifted. It appears that the engine RPM's keep on increasing but the down shifting of the gears are not there.

Secondly when i move the gear lever stick to Gear 4 there is no jurk felt, otherise in recent past it use to downshift one gear.

What could be the reason. Are there some relays to check or something else. Have changed the gear oil along with the filter. But no change