We have delt with the same problems. We warm our spindles for at least an hour prior to running long programs.
103 degrees F seems normal. Our Fadal service rep. always told us "warm to the touch". Of course this was when we were dealing with a spindle that was so hot one could not touch it. They (Fadal) never could fix that machine.
Maybe the new Fadals use a thermal compensation similar to the Red machines made in the USA! I recently ran a mold for 36 hours straight run time on one of our Red machines. Z height was not off more than 0.0002".
Jeff Lange
Lightning Tool & Manufacturing, Inc.