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So back to "science". The above is what I have read/understood more or less to be the toe-in mantra for many years. However you mention "forces at work" What exactly are those forces? And are they speed dependent ( ie wind drag, tire slip, brake drag, etc) and if the main purpose is to allow suspension compliance until zero toe is achieved, what magic happens that stops all this compliance when zero toe is achieved, but the forces continue to rise as speed increases, or is it just zero toe at one set speed, and toe out above? Is this the basis for 11/16" TR? If tire slip was the main force, it would seem to me that as soon as zero toe was reached, the force would diminish, suspension compliance would return wheels to toe in and the process would start all over again, not an ideal situation.

Anyone?

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Really? I'm suprised you would ask this question after posting the initial write up. But, I'll bite.

The force is friction. The motion of the tire rolling over the road creates friction that pushes the toe in to zero toe, if it has been set properly. It is simply to take up tolerances in the myriad assortment of components in the steering system. If you wanted to get precise in it all, you should probably measure how much deflection a system has and use that to determine exactly how much toe is required. In a competition car this may be worthwhile, but in a street car a general range should be sufficient.

This friction is always present and it is not elastic in such a manner that the tires are constantly changing back and forth once in motion. If your sitting still and sawing the wheel back and forth then you may remove the force to a degree, but friction is always there to sufficient degree need the effect. Yes, the force does increase with speed, but once all the slack is absorbed, additional speed does not create additional toe, unless components are worn or failing. It is a hard stop that keeps toe in spec so long as the components are in good working order. That is why analysis of tire wear is the best tool an alignment tech has to get a car dialed in. Wear is a better indicator of what a suspension wants than actual specs can be. On my competition cars, wear, via temperature measurements, is what we used to dial in these specs to create an alignment that allowed maximum tread contact with the road surface for the intended application.

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Suprised? That seems to happen when I shoot from the hip

I think what you are saying is there is enough rolling resistance (friction?) alone to take up all the "slack" in a toe in configuration to result in zero toe. Does that then mean for all intents and purposes static toe in use causes no additional tire wear?

Anyway a previous poster mentioned "give", I then used "compliance", and you used "slack", which probably is the most descriptive in this case. So the slack is considered the only variable that toe needs to correct, and that slack is from only the wheel bearings, the 2 outside tie rods, and the 2 inner tie rods, on a typical mopar? Wouldn't a simple robust bungie achieve the same result?

So does Strut bushing compliance play any part in toe setting as the LCA moves front to rear, or do the tie rods keep the toe consistent?

And to others, I am only discussing the mechanics of this, not sure how that was mis-interpreted, I'm not suggesting anyone make any changes for any intended result.