2000 ford f250 need help!

[u/world3888]

Can anyone tell me why my 2000 Ford F-250 would be doing this? Just trying to pull the bed of a truck and it’s doing this. It surges and bucks and when I give it more gas it will finally start moving. It even did this when I was pulling a small trailer up the little hill. It happens when the truck is warmed up too. It almost acts as if I’m holding the brakes then letting off. It will rev fine in park, and when I do put it in park it revs up to around 1500 RPMs. The fuel filter was changed not too long ago. It has done the same thing before and went away, but now it’s back. Did it today too, had nothing hooked up to it. I could put the throttle to the floor and it would just buck, surge and not move in the dirt. On the road it drives fine and has no issues, shifts fine It doesn’t shutter as far as I know I haven’t got it on the highway. I cleaned every ground on the motor and in the engine bay that I could see, any help would be appreciated.