A sales rep sent me a power point show of this machine called "wheres my dozer" it went through a series of pictures and eventually showed a D-6 or 8 CAT stuck, upside down against the hub of this beast, it looked like a match box car. Aperantly the operator got to close and the bucket scooped it up until it was lodged against the hub. If I find it again I will post it.

found it!
http://sprinklerdoc.com/dozer.html