heres the diferent track sags
the first one is on a Panther D
the second is on a Panther G steel wheel
the third is a Panther G at Aberdeen as in Muzzelflashes photo (rusted tracks)
but the Forth picture is of a Panther G that was captured and used by the British, it must be moving or on rough ground becouse the tracks are toutching the last wheel only
so in the end its up to you what you want the tracks to look like, i will just look at a photo i like and copy it
all the photos are from http://www.achtungpanzer.com/pz4.htm#panther