FZJ80 Steering Box Adjustment

[rover67]

Hi All,

I'm running into some issues trying to adjust the steering box in the 80. I thought I was going to be smart and take up some free play in the steering by tightening the preload screw at the top of the box. I proceeded to adjust it without reading the manual (RTM) and I think I got it too tight, not it won't "loosen" and the steering is heavy and doesn't even come close to returning to center. On other boxes I've tightened I used the preload screw to take up slop then checked for tight spots on the extremes and loosened until they went away and it yielded the best adjustment across the range.

What I did:

1. With the box centered and out of the truck I loosened the locknut on the steering box and screwed the preload screw in quite a ways until the screw felt like it was bottoming out (tight). I was surprised it went so far before tightening up and immediately was like, whoops.
2. Turned the input shaft with a pair of pliers to feel the resistance and check for binding, I didn't feel any binding but the steering felt tight across the board. not horrible, just kinda tight.
3. Loosened the set screw to try and loosen the resistance on the input shaft
4. Felt no improvement
5. Got out the manual and tried to follow it's instructions which said to tighten the screw until a certain torque was reached but not to exceed. (forget the exact verbiage). my torque to turn was higher than it said it should be, but not by a lot.
6. Tried loosening it again and it still felt tight and never loosened up.
7. Guessed at the setting and left it and figured I'd drive it to feel what it was like installed.
8. Steering still feels tight and doesn't return to center, no real slop. proceeded to drive a tank or two to see if it'd loosen.
9. Loosened the set screw a few times over the course of those last few tanks to try and get some looser feel, both times it didn't change the feel of the box. It was like I did nothing. box didnt even feel sloppier in the middle (free play non existant)
10. Use the google machine and find this thread : https://www.landcruiserclub.net/community/threads/adjusting-80-series-steering-box.139249/
11. I think maybe where I'm going wrong is i am turning the input side to feel for tight spots rather than turning the output side?
12. Somehow it's stuck and won't loosen.

Does anybody have any experience setting the 80's steering box preload before I try that link's instructions and get after it and attempt to re-read the manual and try it's method again? How do I get it to feel looser again?

 

[60wag]

The adjuster screw pushes on a plate that sets the preload on the outer race of one of the output shaft bearings. Maybe the race is sticking in the bore? Loosen the preload screw and tap the output shaft toward the adjuster screw with a mallet - that might loosen it a bit.

 

[rover67]

The adjuster screw pushes on a plate that sets the preload on the outer race of one of the output shaft bearings. Maybe the race is sticking in the bore? Loosen the preload screw and tap the output shaft toward the adjuster screw with a mallet - that might loosen it a bit.

that was my next plan, BFH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[KC Masterpiece]

I wonder if it would help to disconnect the steering linkage to the pitman arm so it is not under any load while being adjusted. I remember when I tightened mine up it took less than a full turn of the screw to get a good result. Otherwise you are going to have some weight pulling down on the output shaft.

 

[jps8460]

Definitely try loosening the adjusting screw and tapping the bottom of the cross shaft with a mallet. And see if it frees up. You really shouldn’t have to tap super hard.

The ball screw that the power piston rides on will give way to a lot of interference with the cross shaft and power piston ie 0 backlash condition. It’s hard to push through it by hand, but once the valve has fluid pressure, it will push through it and f up the ball screw

It’s possible that the locknut on top of the cross shaft has come un-staked and has allowed a bunch of thrust clearance and that is not allowing any real adjustment anymore. Popping the top cap off and checking that is a bit messy but fairly straightforward.

 

[rover67]

I ended up throwing a jack under the pitman arm and pushing up on it with the screw backed way off and was able to free it all back up again. With Allison wobbling the wheel back and forth to feel the free play I slowly tightened it up to find zero again and all is good!!

Thanks for the guidance folks !!