Steering box adjustment nut too tight to remove?


TJ Enthusiast
Dec 27, 2021
Western Australia
'99 RHD low mileage (65K) TJ with 31's. Slight slop in the steering (not awful but noticeable) so thought I would adjust the steering box as all the other parts of the steering foodchain seem OK and no obvious worn bushings etc.

I cannot shift the lock nut on the steering box. It appears to be a nyloc nut with the allen key centre. I've cleaned the outside of the nut off and even tried a spot of penetrator fluid but its just not budging. The angle and space constrains how much force I can use but I felt like I was going to break something if I went any harder.

There is no sign of corrosion anywhere on the box and apart from caked on grease and dirt which has been cleaned off nothing else that looks amiss. I'd hazard a guess its never been off.

Thoughts? I can live with it as it is if I have to but would be nice to tweak it just a smidge (noting all the dire warnings about overtightening!)
From what I've been told that "adjustment" nut isn't for "tightening" steering slop. It's for setting the initial lash after manufacture. The bore on the steering box gets worn causing the slop and the only solution is replacement with a new manufacture box or a remanufactured box with a bore that's not worn out.
Yep from multiple sources I've seen you can use this to tweak a slight amount of slop out by tightening the lash in effect, but its not a magic solution and cannot be tightened multiple times to resolve an underlying issue. So its a very small adjustment range.
Have a close look at the threads that should be visible at the top of the nut. I've had boxes with standard and reversed threads there.
Proper adjustment should be done in a vise, after the input shaft thrust bearing has been adjusted.