[dmay]

If you deal with heavy snow falls (=>2ft) I would recommend chains on the rear. Just set your blower skid shoes to leave a snow base so you don't damage your driveway.

 

[dmay]

I think everything you add makes a wow difference. Add a ballast box and wow what a difference. Add chains and wow what a difference. At least that is what I experienced. I tried without chains at first as well. All worked well until the snow got to be 3 feet deep. Then after getting into a few inclined spots where traction became an issue I decided to order chains. Wow, what a difference. However I deal with a lot of deep snow for a lot of months. Your experience may be different. If you have lighter snow falls, flat ground, no inclines or a heavier tractor you may have no need for chains at all.