Front Suspension Bottomed Out

steptoe said
I have a problem with the front end of my '75 Dart bottoming out. I mean sitting on the bump stops. Looks like a car without any bars installed. I have new shocks and rebuilt the upper and lower control arms with new bushings and ball joints. Didn't help. I can adjust and set the ride height to a normal stance and bounce the car repeatedly. Everything is fine UNTIL the car moves forward 5 - 10 feet. The front end immediately drops until it bottoms out. Jack the car back up until the weight is unloaded and sit it back down - it looks fine again. Move the car 10 feet and it drops again. I have to suspect it's a torsion bar or mounting problem. The bars appear to be OK and the adjusters are working. I also looked under the car while it was bottomed out and the torsion bar adjusters are still lined up on the bars. I had suspected they were jumping off and allowing the suspension to unwind. I guess whatever it is requires the tires to move which allows the suspension to change. Remember the old Volkswagons? Jack up the rear end and the wheels tucked under. Sit it down and they stayed tucked under UNTIL you moved the car. Then the wheels would return to normal. This is what I have going on. I cannot find anyone local who is familiar with torsion bars but have read that the front or rear mounts could be rusted or damaged. I cannot find any rust or damage. Could the bars be slipping in their hex head mounts? If so, would they only slip when the car is moving?

Do you have the upper control arms reversed (wrong sides)? This will cause the car to do what you are describing. And contrary to what some say, they can be put on the wrong sides. Another possible culprit is excessive toe-out and/or neg camber. Have you had the front end aligned?

Once it has dived after driving that 10 feet or so, back it up and see if the car returns to normal stance. Severely dragging brakes would cause something similiar to this.

Torsion bars would not cause the problems you are experiencing. If the bars were weak, you would have to keep adjusting them up each time it got low. The chances of the bar turning is the socket are about one in a million and if it turned, you would most definately hear it. If the t-bar cross-member is damaged or rotted you would be able to see it and know it was the cause.

Larry