Newly converted 9spd to 13spd issues

Since 13’s are just 9’s with a compound box on rear. Throughout history there have been plenty of trucks that had 13’s factory installed that were converted to 9’s due to different rear gear changes over time. So it can go both ways.

 

That's a vent on top. If it's leaking continuously, the o ring has failed.

Not a hard fix

 

Yes, when it has air it leaks, the o ring has failed.

 

Rebuild splitter and range cylinders with new Eaton o rings.

 

This was actully a bit of an issue with my pete when i first got it though a little diffrent. The way they had to set up and the engine set was in the 900-1200 range with RPM limiter set and the horses limited way down to iirc 430 horse to cut off at 1300 rpm with a peak torque of 1550 though in practice i couldnt get it over 1400ish (who ever owned my truck did a lot of really weird ####). I had to have the engine adjusted to 455 and the limiter removed so i shift in the 1200-1500 range so the splitter would work correctly.

May not be YOUR issue but worth looking into at least. And if they have it set that low and it can be safely uprated have them ensure the Ujoints and shaft are actully rated for it so you dont pretizlefy a driveshaft like i did lol. Also see if your 13 speed is rated for 1850. Mine wasnt but if yours is you can push to a 485 horse tune and your truck will work a lot better.

Again this may not be YOUR issue as MY truck had a lunitic program it....but worth having looked at.