Zebrafive,
Thank you for your reply. I am still curious though, beyond the difference in appearance (the larger tires making the tractor look larger) was there a substantive reason for wanting the smaller tires: lower center of gravity, barn door clearance, etc.? I ended up upgrading the tires on my 5085M from the 12.4R24 / 18.4R30 combo that came with it to 14.9R24 / 18.4R34. The idea is to have as large a footprint as possible for less rutting in the muddy fields. So far I have gotten almost no seat time because I had to wait for the loader to arrive to begin to actually use the tractor for late winter early spring tasks around the farm. I must say that although it is a 5 series tractor, it is tall and looks quite large with those tires on it.
Thanks,
Island Farmer