Hello Thom,
There are one or two things you'll need to do alignment wise before you can
eliminate it as the cause.
When doing an alignment, it is critical to get the thrust angle correct or you
can end up with a shimmy like you describe.
The thrust angle is the effect the rear axle has on the steering of the car,
much
like a wheel barrow is steered from the rear.
The rear axle centre-line, and front axle centreline MUST be parallel.
This is where professional aligner gear is hard to beat.
The other factor is front wheel set back on either side.
OK, Try this: Make sure the steering wheel is straight when the steering box is
half way between full left and right lock. Now, lock it in that position.
Now you'll need a long straight edge from the rear wheels, to the front wheels.
Get them so they're exactly in a straight line.
You will have to allow for track width difference, and any variation in off-set
of
the rear axle centreline, to the cars centreline
Measure the distance between the front and back wheels on each side.
I'll bet there is a difference. That possibly is where the shimmy is.
Often it is much quicker and easier to get it done at an alignment shop, and
they
can set it up and give you all the base line data, i.e. setback, offset etc, so
you
make minor adjustments at the track.
Also you must balance everything in sight. especially the drive shaft, and yes
rear
wheel balance is critical.
Other possibilities are soft or broke tire cords that only show deflection
under load.
> That's what this TR3A is
> doing to me...and it's spooky as hell. I really don't want to simply give
> up and return the car to the owner, with the same ___king problem he
> originally wanted me to fix...knowhutImeen?
Sorry for such a long reply, but alignment is so much more than just front toe.
Regards,
Bruce.
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