I think I'm going crazy but at times my truck pulls to the right then to the left. I don't think it is going to be raod related. Tires were switched out as well. At times it wants to pull slightly to the right, then if I "lightly jerk" the wheel to the left then it's OK. Happens the other way as well but less often. My truck is a 2001 F250, SD, PSD, 4x4, CC, 8', Auto.

Could it be something to do with the anti sway or 4x4?

 

Sometimes certain styles of tires are really bad about road walk, this is never to pull the same way either, sometimes to the right and the next to the left.

Something else I would do is get someone in the cab, have them with the key on but the PSD not running; move the wheel back and forth while you lay under the truck and check things for to much slack anywhere...

 

If it's a slight pull in either direction, then it will be "road walk" like Rowdyone said. Put on some wider tires like mine and you'll feel it all the time.

 

I went from off road style tires to my E series Michelin tires. Could there be something with the front (for lack of a better term) steering stabilizer shock?

 

To much air pressure wil do that too. For my truck 50 psi in the fronts and 45 in the rears seems about the best, If i bump them up to 55 or better my steering gets funny also, even did the chalk test and tires roll almost perfectly flat with those pressures too.

 

The type of road surface also makes a great difference in the amount of roadwalk.

 

I had some steering wander too, I adjusted the free play on the steering box and it got rid of 90% of the wander. It's that allen bolt and lock nut on the top of the gear housing. Adjust it down to tighten. Don't go any farther than feeling the adjuster making contact.

 

I believe fomoco calls your concern memory steering. I had the same problem earlier on. Its caused by your ball joints.(stiffness with the joints) They came out with up dated joints. You may want to like into that. Hope that helps.