eaton fuller 18 speed need correcting

I need help on my eaton fuller 18 speed. I just bought a 98 peter 379, cat 3406 with eaton 18 speed. What I'm trying to find out is that every time I spilt the gear, my rpm jumps up higher. Example gear 1234 switch up 5L (rpm 1600) spilt 5H (rpm jumps to higher by 200 rpm) and so on. I want to know is this correct or did the previous owner swap the spilt switch air hoses.

 

Yup, splitting it forward is like downshifting it (higher rpm). If I start with the split in the forward pos. and split it back pos. it goes into higher gear (lower rpm). I hope that makes sense.

 

Thank You. I'll post some pic up soon. I was thinking that's the way the splitter gear should work.

 

I try switching air lines on the shifter and all it did was release air from the shifter and it didn't split any gears. I thing the air line from the shifter going to the transmission is backwards on the transmission. so I'm going to switch the air line see what happens.