Box being too tight at the screw on the top just makes the truck want to go any direction BUT straight. Get it too tight, and your over-center steering (trying to go straight) will be impossible.

I think you would be much further ahead REPLACING that box.....

 

it is hard to keep straight.. I may have to replace the box.. I got the arm off, removed the four bolts around the adjustment screw, and tried to pull that shaft out, but it gets about an inch and stops dead.. will not come out..? I printed off a couple guides on this, and they all say to pull it straight out.. Not happening..

 

The procedures in the manual. If I remember it says something about counting the number of turns it takes (with a wrench, or something of the sort) from stop to stop. Then turn it back half the amount of times you just counted. Ex. You can do 12 full turns of the shaft from when it stops, going counter-clockwise, to when it stops, going clockwise. Half that number is 6, so turn the shaft back counter-clockwise 6 turns and viola, out comes the shaft.

Yours probably won't come out because you must have spun the shaft around instead of immediately pulling it out.

 

That sounds about right.. I turned it slowly and pulled most the way, it came out eventually, but still not easily.. I had to tap it, very carefully I might add.. Any way its over and done with, besides the hassle of getting it apart, everything looked almost new..? Gears and bearing nice and clean, no rust.. No shavings or chipped teeth.. So I readjusted the whole box, put it all back in.. No more leak.. The seals were actually EASY to do.. with the exception above.. I still have to tighten the box, but otherwise, it drives MUCH better, and doesnt leak!