larryscar

I am having a problem with my 1999 Forester. Mechanics are stumped. It runs fine for the first 10-15 miles, and then begins a slight vibration which continues to get worse and worse. When climbing even a slight hill, it will start vibrating violently. The whole front of the car will start shuddering. I've replaced the drive shaft and the top oxygen sensor, but did not resolve the problem. Fluid level in the trasmission was low but topping it off did not help. Replaced spark plugs and wires. Any other ideas??