40 crawler with trencher

[rvbarkley]

Noticed in the little pictures that pop up what looks like a 40 with a trencher mounted on the back. Has anyone ever seen one of these ? Was just wondering how they slowed the crawler down when trenching. I have a Cub Lowboy with similiar setup, (Auburn trencher). It has a reduction unit added before the transmission that slows it down to a barley noticable crawl. (have been looking for replacement digger chain for a long time?)Roger

[Lavoy]

The pic is of a 430 with an Auburn trencher. They had a special transmission that feeds power backwards in through the PTO shaft from the trencher to drive the crawler slower. It also had a sort of "torque converter" that would allow the crawler to speed up and slow down slightly depending on how hard the trenching was.
The only crawler we have ever known about with this setup is less than an hour from me. I redid the tracks on it a year ago.
Lavoy