Originally Posted by MNSmith
I would also say, as an added safety measure, chock the wheels.

Chocking wheels or setting the brakes is a definite mistake. The vehicle must be able to follow the movement of the jack arm, so always have it free to roll- - - -trans in neutral, brake released. Otherwise, there's a possibility of pulling the jack off the lift point since there's no way to follow the slight fore/aft movement of the jack pad.
Jerry

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