Steering Problems with Trailer

[NCBBQ]

I have an '02 f250 powerstroke, single axle, crew cab, 8'bed. I have 2 different trailers I pull with this truck. I have a problem with the power steering while attached to the trailers. It's almost like the power steering is gone at certain points and I really have to crank to get the weehls to turn. Took it to a local dealer and the lubed the fron end and said they couldn't find any problems with the gear box nor power steering.

A friend talked to someone and told him there may be a power(electrical) issue with the signal going to the power steering with a trailer attached. Said it may be cutting the power and causing pump malfunction.

Anyone ever had this or hear of similar problems? If so, any fix? I neeed help because this is a real PITA. Thanks bunch in advance for thoughts/ideas.

[Aggie007]

Mechanical linkage from steering wheel to steering gear box, so electrical shouldn't be it.

[NCBBQ]

I've been told to look into the power steering pump as there is some sort of an electrical assist that the trailers may be pulling from causing the issue. I'm grabbing at straws here.