The Lowest gear for the R151-R150 trans is either a 4.30 (Stock Turbo R151 trans) or a 5.15 from a Hino truck. We have no clue as to what the trans from the HZJ79 looks like.
Much less ever seen one in person. Heck if you what us to figure it out ship us a truck and we will see what we can do. Be sure to put attention "DEAN" on it... sorry we couldn't help.......... Dean
