I just reread your original post and I totally missed the most important thing that you said and the cause of the problem. When you drive a 13 or 18 spd transmission, you don't pre-select the splitter like you do the range valve or this problem you are having will occur. The splitter will not wait for you to let off the throttle to shift, it is instant as soon as you hit the splitter so you have to be off the throttle when you hit it. If I were you, I would put it all back together and try it before you try to fix anything other than your PTO installation.
Splitter is located in front end of transmission. Can you post transmission # ore get manual on Road Ranger site?
This is incorrect. Range and splitter shifts have been pre-select for years now. Splitter can't make the shift while the driveline is under torque.
I just had a reman RTLO18918b put in my truck about a month ago and it is doing the same thing to me. Just in 5th, going from low to high it will slam in and from high to low so I can shift to 6 low it will sometimes grab 5 low and BANG. This is extremely frustrating . I have worm motor mounts that I thought may cause some slop and allow this to happen and they will be changed today. The splitter assembly on the back of the tranny is leaking oil. I have to have the gasket replaced. Can I tell the shop to replace the pressure regulator when they are in there ?? is that where the pressure regulator is located ?
Also I've noticed that if when in 5th I flick the thumb splitter back and forth a few times before the shift it is less likely to happen.
The pressure regulator is external on the trans. Now would be the time to have them install a kit in that shift cylinder while they have it off for gasket replacement. It could be dry and hanging up.
Flicking the button would preload the shift cylinder with air prior to the shift which would indicate a dry cylinder/piston/o-ring and possibly hanging up during the shift until it builds pressure.
Well I called Peterbilt of Fargo today and I talked to the service man there. I told him how it slams and the first thing he asked me was has the truck ever sat. I told him yes the truck sat for over a year straight. He said that if they sit the moisture in the lines and from humidity well cause the valve assembly to rust on the inside. He said he has seen it before. He said I could try shooting some mineral oil in there and seeing if that works. Instead tomorrow I am just going to order a new regulator/ filter and splitter valve. Between that and fresh tranny fluid (the last stuff was burnt) I am going to see if that will do the trick.