Good day- I have a problem with my 07 Mack CXN613. I have recently developed a shake in the front end. I brought the truck in and had it checked over. The tires were chopped on the inside edges. The king pins had some play and were replaced. One the rear spring pins/shackles had some movement and both side were replaced right away. At the time there was a very noticable leak from the steering gear box. After the king pins, spring pins, and shackles were replaced the truck seems to want to wonder- steer right and correct to the left- then steer left and correct to the right- constantly fighting with the wheel. The leaking gear box was replaced and the problem went away for awhile. Now after 30 miles the fight with the steering wheel is back. Any ideas? Thanks