my 05 regcab had a bad understeer condition since new.well its gone, not sure if its the new tires or new z code front springs,but it turns much better so far.i posted a couple days ago that ford was replacing my tires due to unevenly worn tread.its one of the tsb's, i had hankooks they were awful.well they found more hankooks so i traded them to a local tire place and got the tires i wanted for 200 bucks mounted and balanced.the springs were installed today also the labor was $88.00 .

 

Chances are your alignment was off. Toe-out on turns is a major contributor to Over/Understeer. If your alignment was off, it will not only wear tires but cause these conditions. You had it aligned correct??

 

they gave me some line about try it see how it is when i asked about the alignment.i will get it done this weekend somewhere else i can trust.

 

When the dealer replaced the Hankooks they also did an alignment. That is the primary purpose of the TSB. By changing springs and tires I would definitely get the alignment checked again.