Transmission problems
 

Ok I have a 1997 dodge 2500 I recently pulled out my power steering pump to rebuild it since than my truck will drive fine for about a mike than it acts like it kicks into neutral and will creep ahead slowly sometimes when it happenens I have no idea what it could be te transmission only have 15k miles

I would assume we are talking about a 47RE? not an RH, sounds like the trans is loosing pressure to apply the clutch pack. If you manually put it in low or 2nd does it act right then?

Yes it is a 47re and no it does the same thing in every gear

If the fluid level is correct I would look around the truck and see if something got disconnected during the recent maintenance.
Check wiring.
Is your Tach working?
Did you install a new converter during the trans swap?
Since the trans isn't very old I wouldn't think bands or an adjustment.
Could be a Gov solenoid maybe.