I sold my 18" Touring wheels to a gentleman in Washington state, and wanted to make sure that the wheels would survive the trip. I found that by using two 20 X 20 X 20 boxes and two large pizza boxes (in between the pairs of wheels in each box), everything fit nice and snug with no box-stretching or wiggle room.

Just wanted to make my little contribution to the Z community!

 

The key is the type of box construction, and the specifications are usually on the bottom of the box. In other words, don't put a 25 pound wheel in a box designed for a maximum weight of 20 pounds. Snug is fine - just have some cushion at the edges of the wheel. That is most likely a critical area for shipping damage.

And of course take photos BEFORE you ship.

 

You wanted photos of the pizza boxes, didn't you?

 

Ship greyhound cheaper.The wheels will be happier.

 

I did that once with a bumper cover from NH to Florida and it was only $40. I figured that was pretty good considering the rear bumper cover for the Z is enormous!