2004 Ranger-jerking-heitation-tranny or eng?

I've got a 2004 Ford Ranger 4X4.Automatic transmission,4.0L,3000 miles.When I first get in the truck in the morning and get going down the road I get a slight jerking and or hesitation,seems like it's happening the most in 3rd gear.After the truck gets warmed up it runs fine.I noticed it was worse in the winter.But now that it has warmed up its not as bad.Can the dealer correctly diagnose this by hooking it up to the computer.Does it sound like the tranny or engine? What should I do ? Thanks!

are all the fluids full? sounds like the tranny might not be getting fluid till the fluids get hot and expand.

bikerboy