I contacted jody at DP. Few days ago. Just got reply. He said its in the gem module or security module in 2002 up. Said it would have to be programmed by dealer?

 

Another internet myth comes to life. Need a high pressure oil pump too? Sorry, not relevant to this thread. *Slaps wrist*.

So long as you have a PTO transmission (correct hard parts and valve body components), the PCM is the only thing that cares about PTO inputs. Yes, Pin 66 gets 12 volts but ONLY AFTER A PTO RELEARN has been done and this involves killing the power to the PCM for a little while and erasing any RAM that has saved current PTO option data. Then as you perform a short drive cycle, the PCM watches turbine shaft speed read from the different coast clutch drum vs. output shaft speed to determine if the transmission is a PTO model or not. Once the PCM learns this and power is not interrupted to the PCM afterward, you should be good to go.

There are a lot of references on the interwebz about how the PTO stuff is supposed to function and what operating characteristics are to be expected and are allowed during PTO operation. These two links have a whole bunch of good information in them.

https://www.parker.com/parkerimages/...TO-TEC-116.pdf

https://www.munciepower.com/cms/file...ll/IN97-05.pdf

 

On the periphery. I was part of a team that provided transmissions to an off road race team. During the life of the 4R100 that was what they used.

 

Thanks Cletus and Mark. I did read few places that gem module has axle gear ratio or tire size programming. Is that a myth?

 

It may, but if it does it is only for the speedo/odo. The PCM doesn't look at that.