I just replaced the steering box and all the rods from the box to the
wheels to fox this problem, it did nothing.
Truck has 200,000 miles, if I hit a pothole with either left or right
front tire, the entire front end starts shaking and it increases to
the point the truck might break or wreck. It started at highway speeds
like 70 when hitting a bridge seam, over a few hundred miles the speed
at which the problem would start was lower and lower and now if I hit
a pothole at 35 it will start this wild shimmy.
I think the entire differential is actually moving forward and
backwards when I hit the bump and the mass of the diff bouncing off of
whatever combined with the friction of the tires on the road provides
the means for the oscillation to increase to critical mass.
What is worn out that could cause this to happen ?
I noticed that the differential seems to have some lateral movement to
it when I turn the steering wheel left and right while parked and the
front of the leaf springs move left and right opposed to the movement
of the wheel, they are moving not in their mounts, but the mount
itself is moving up in the frame where I assume it is bolted in with a
rubber piece. Don't know if this movement is the problem or just a
syptom of something else that is worn out like a sabilizer bar or
There is a bar that runs behind the front differential with a lot of
bends in it that connects to a smaller rod on each end that connects
to the frame, the main bar is connected to the differential via a
mount with rubber in it.
The is also a shorter bar that connect the differential to the middle
of the frame, this bar is on the right side only.
None of these is obviouly worn or loose.
If I drive very slow over a rough gravel road, I can hear and feel a
slight banging as if something is moving and hitting its stops, I can
feel it via the steering wheel slightly but the entire steering system
has been replaced and there is no play in it at all.