just had my rear tires rotated to the front with 85% tread xterrans and put new xterrains on the rear and now the truck has very touchy steering. when you do a lane change at highway speeds and get in your new lane it wants to swerve back into the other lane. if you let it wander in your lane and correct it it wants to swerve off the road. Alignment was last january and they replace and inner tie rod at that time. i dropped the air pressure they had 40 psi and i dropped it to 30 psi where i usually run them for highway use. Any thoughts or where should i start