Sundstrand hydrogear vs piston to piston

[cafoose 3,355]

I have a GT-14 with a piston to piston and the gear case is cracked and leaking near the drain plug. I have a donor GT-14 hydrogear and would like to mate the gear case with the diff and axles from the donor to the rest of the piston to piston hydro. In other words, I want to put a hydrogear diff and case on a piston to piston pump and motor assembly. Will this work? @pfrederi @daveoman1966 I have several GT-14 tractors and most have hydro gear. Two of them have piston to piston. Posts 43 to 45 in this thread describe why I want to do this:

 

 

 

[953 nut 55,744]

15 minutes ago, cafoose said:

I have a GT-14 with a piston to piston                   This confirms my belief that the piston to piston will fit.

I was told years back that a piston to piston hydro would not work in place of the hydrogear but am of the opinion it is worth a try. Pull one of each and lay them side by side and see how close they are. If the output gears are the same size it should bolt right up. The gasket for both is the same so it is a matter of getting the gears to mesh. Could be the driven gear from a "C" or other Piston to Piston unit was substituted. Left transmission case halves are probably interchangeable.

[Handy Don 12,444]

I applaud your determination to keep it running. 

Following and best of luck!

[pfrederi 17,864]

Should not be a problem but as Richard points out count the gear teeth on the hydro motor.  GT14  transaxles had different gears than Charger  and early C series.  There is a thread on here by Aldon showing how to replace the out put gear on a hydro gear motor (not from a GT14) to match up with a GT14 transaxle