Early 1999 F450 PTO setup.. remand trans but looks to be stock converter.. 4x2 cab and chassis.180k for miles.. this truck is stock no chip no upgrades. Just tires are larger 255/70/22.5.. Maintained Well.. . Trucks used as a hauler. Daily it will have two carS at a time. 22k 26klbs total weight with truck and payload. I’ve done a lot of work on this. there is so much on these to trouble shooting.. all my issues with out throwing money at it. I have fix.. all service engine problems are corrected.. no OD light flash besides Over temp happed a couple times.. I have a banks temp gauge on it now. I found last night my cooler and lines were cold. Has low line pressure said snap on scanner. This rig is acting identical to brake switch on ( brake peddle pressed ). I’ve done the 69 hit brakes and hold nothing happens. No change. If I hit the OD button it will down shift then go right back if I stay in same AP position. If I easily press a little more it will high rev. With a lot of converter slip. 3rd will hold steady with 100 converter lock unless I let off. Then it will try fourth again. If I run in drive. No issues. well besides the cooler not getting fed trans fluid. Well the low line pressure. 😕... I also have a leak in my fuel line don’t seem to effect engine, but as I’ve read can’t take nothing for granted.. so handling fuel leak tonight. Thank you all ahead of time..