king pin inclination angle is measured 90 degrees from the caster angle.
It is how much the king pins lean in from vertical.

Don't have an answer, but sometimes the left and right side angles will vary a part of a degree to account for the curved surface of the road and which side you usually drive on.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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