Regular tile is pretty strong but porcelain is heinous strong. Properly set, I have read porcelain has a strength of something north of 10,000 psi. Most jacks have wide wheels on their lifting end and spread the weight out really well.
A couple of our tile members who have regular ceramic tile installed report no issues jacking up their vehicles.
I suppose if it really bugs you, you could use a small piece of 1/4 Masonite or 1/2" MDF under the jack when finally positioned.
I figure that is what I have six boxes of spare tiles for. If I ever crack one, I'll pop it out and replace it and no one will ever know a tile was replaced.
Try
that with epoxy!
