I have a 1997 36' Dolphin M.H. and it has a tag axle and there is not much more that I could say about it then what the other thread have already said.
But there are a couple of things I would like to add to this discussion.
No. 1, The tag has a break system all of it's own it even has a master cylinder which I forgot about and it cost me around $2,300.00 to have it repaired,
so when you have them check your break master cylinder for fluid be sure and tell them to check the tag axle master cylinder also. Not all repair shops are aware that some M.H. have two.
No. 2, In California when you go over a tole bridge with a car in toe the fee for that will be $25.00 (as of now) they count the tag as an extra axle.
Just a thought