Ford 3000 (1971) front wheel shimmy

[88xjwheeler]

Hello- welcome to my first post on here!
I have a 1971 Ford 3000. It operates fine for slow driving activities, such as mowing, grading, dirt moving, etc...
However, if I try to drive it down the road, even at modest speeds of 10 to 15 mph, the front tires sometimes shimmy back and forth violently. This seems to start with the encounter of any eneven surface, such as a transition from pavement to gravel, pavement to bridge (I live on a gravel county road), bumps in the road, small pot holes, or even heavy gravel on one side, and little or non on the other. Observations I have made- it is more likely to happen if you are trying to go stragiht- ie, the steering wheel in more of a neutral position. IF you turn slightly either to the left or right, but without actually causing a turn, it greatly lessens the problem. I am thinking internally the steering box has a lot of play in it, or maybe the power assist cylinders have some air in them.
Any insight on this? mods- if there is a more a ppropriate forum on TBN, please move my post to the place that will get me the most accurate answers.
thanks all!

 

[qstott]

My JD 1050 did that when I replaced the front tires with new ones. I adjusted the toe in so the front on the tires were about 1/4" closer than the rear. It got much worse. So, contrary to conventional wisdomj, I set the toe out about 1/4", and it stopped the problem.