The Cummins and AISIN are TRUE Medium duty. You say so are the Ford and GM diesels? Are they used in other Medium Duty application other than GM and Ford? Cummins and AISIN are used in many different MD applications.
The head West Coast Warranty rep for Chrysler Stan Gozzi was asked a couple years ago about the AISIN he said "they don't break".
I tow 33-35,340# West coast with ZERO issues. My hottest trans temp while idling in miles of stop n go recently with this load was 172. The hottest while climbing miles of 6 percent grades was 167.
