'97 F250 HD. 5sp, 4x4. Firestone transforce tires at near max psi.

When I turn my front tires are making a funny sound and it almost sounds like I'm in 4x4. Hubs are manual set at free, in 2hi. It doesn't sound/feel exactly like it does when in 4x4 on a hard dry surface, but that is the closest thing I can describe it as. Really only noticeable a slow speeds, like in a parking lot. Can't feel or hear anything out of the ordinary at any kind of speed.

Truck is running great otherwise. Pulled my little 5er this wkd no problem.

Just had a shop change fluid in transfer case, and front and rear diff.

 

One of your manual hub locks may be stuck and spinning your axleshaft. That would make it feel like you were in 4x4.

Check by climbing under with the truck off parking brake on. Twist the front driveshaft by hand, if both front axleshafts/ujoints are spinning, then it's not your hub locks.

 

Just to clarify, this is a tire sound right? Not a drivetrain noise?

 

Yes, it seems to be coming from the tires.

A couple years ago one of the hubs wouldn't lock. A mechanic friend helped me get it to lock. I wonder if this is the opposite problem now.

 

Unless you have a limited slip front end, it really shouldn't matter. Having one hub locked in 2hi shouldn't really be noticeable. My old truck had a LSD front and I had trouble turning in 2wd when it was slick out if both hubs were locked. But It had to be both hubs.

My money is on suspension or an alignment issue.

 

You may have frozen front axle U joints or frozen up ball joints making it turn hard at low speeds

 

could this be checked by jacking the truck up and spinning each wheel at full lock?

 

yes it could

 

Can you explain this to me in a little more detail?

I turned the front drive shaft and both axle shafts were turning freely with the hubs at free.

 

Full lock means you've got the steering steering wheel turned fully left or right.