DIY Front Alignment Troubles

Doesn’t matter, bouncing the front end doesn’t work to set the alignment. The tires have to roll otherwise the change in height won’t happen.

When the tires make contact with the ground as the car is lowered the alignment is different than at ride height (the front suspension travels in an arc). The tires tip out at the tops at full extension, narrowing the track. The friction of the rubber on the ground holds the tire patch in place as the car is lowered. Bouncing on the front end of the car won’t slide the tires across the ground, so it won’t settle the suspension all the way unless you roll it. Unless maybe you’re running bicycle tires on a polished concrete floor.

To do it right you have to drive up onto the turn plates in the front, not jack the car up and slide them under.

It certainly does work with turnplates that have bearings in them. If what you say is true, that means every alignment man in the world has to roll the car off the rack and back on to get the ride height back right after jacking it up. How stupid does that sound?