Ok maybe someone can help with this one.I have a 1985 MB 300sd. With about 450,000 miles on it it has been well maintained and did run like a clock until about a week ago. The problem is the car will not move. The trans is not engaging or something to that effect. It has plenty of fluid and is not burt up I have already checked. It has a new filter new fluid.I think there is a vacuum problem. There is only one vacuum line coming into the trans. However the pump is woriking but the door locks are not functioning.I think there is a leak somewhere but cant find it. Any suggestions will be greatly appreciated. Thanks I confused man.