Okay Black-Sheep,
Grab it and growl.
Here is the link to the only place I know of on the web for the 396pg service manual for the JD 400 hydrostatic tractor. You can view it for FREE. For a few bucks you can download it or print it off. Its in PDF format.
It also contains the rear PTO, MOWER DECK, REAR TILLER and SNOWBLOWER complete info.
My daughter Emma was by for a visit and set this up for us. Dads a computer dummy.
Enjoy, JZM
www.scribd.com/doc/47048636/John-Deere-400-Hydrostatic-Tractor