Sundstrand Sauer Danfoss Series 40 M46 EDC & HDC O Ring Change

They have reconfigured the control housing to take an oring that is stiffer that has a larger cross section. It will require a deeper groove to be made into the housing. So it will not have to have two orings anymore.
The EDCs and HDCs that are the older models will need the smaller cross section orings. When you have to replace these parts, it will have the new parts: stiffer oring with the larger cross section. Seal kits will have both the old and new orings in the kit.

So if you need further assistance with this subject, please let us know
800-361-0068
sales@hydrostatic-transmission.com