Ok, replaced linkages and ball joints.
Steering still has play and truck wanders side to side... a loose steering gear would cause this no? Tires are not excessively worn and brakes are good (not siezing)
Just adjust the lash to tighten it up?
Anybody experience this?

 

How's the "rag joint" on your steering shaft?

if it is time for a new gear box these guys are the best and located in your home state...

Steering Gears | Steering Gearbox | Rack and Pinion | Red-Head Steering Gears, Inc.

 

The steering gear in my '79 had a lot of slop in it. I adjusted quite a bit of play out, but it still has some. If you get it too tight, it can bind when the wheel is turned very far to the side since the gears are most worn and have greater slop in the middle.

 

Having no idea what year / model Ford truck you are working on ... check the bushings in the track arm (panhard rod) at both ends, check the mount bolted to the frame on the driver's side. Old rubber allows the axle to move sideways.

Might be good to just get a 14 piece polyurethane C- bushing kit in 3 degrees and replace C-Bushings, radius arm bushings, and the bushings in that track arm. The added 3 dgrees of caster will make the truck drive better as well.

If you have the pre '78 F-150 with "inverted Y" style linkage, not much to say since you just replacced it. If a 4x4, I'ld have said convert to '78-79 style.

Be careful tightening up on that steering box!