Pitman Nuts.

First, I'll say a few things I know to be true about the pitman nuts (in case somebody finds this thread later)
It is a 1 5/16" wrench size. The torque specification is 185 ft-lbs and the thread size is 7/8-14 UNC. It's a common enough size in industrial applications, so Fastenal should have one on hand.

Today marked the second time I put a wrench on the pitman arm nut and found it way-too-damn-loose. This, with my newborn son in the car. Not Effing Cool. From what I've read on this forum, it's not exactly uncommon, either, to find the pitman nut pretty loose on the shaft.

As I see it, there are three solutions when a split ring lock washer (like the factory supplied) just isn't enough.

One, use loctite. Given that I'd oneday like to be able to remove my pitman arm, and I'm not sure how loctite holds up a a constant bath of PS fluid (what, your box doesn't leak?) I am counting this one out.
Two, double-nut the thing. This is when you take a second nut & torque it down against the first. A full explanation (it's more complex than it appears) can be found HERE. This requires a torque wrench, a 1 5/16 combination wrench & a second pinion nut. If I'm understanding what I've read there correctly, this technique relies on tensile preloading of the threaded member to lock the nuts together.
Since even a grade 5 7/8-14 thread takes 350+ ft lbs to preload, I'm calling this a "meh" option. I read one post by a guy who said he'd used a bunch of loctite & double nutted his buddy's shaft (filth intended) and hadn't had any problems. Probably the loctite but maybe a sub-optimal double nut would help too.
Three - switch to a metal locknut. This is the way I'm leaning. Fastenal is closed Sunday nights or I'd be there right now.

Hopefully this is helpful to somebody, at some point. The take-home AFAIK is this: spend $15 at fastenal and get a locking nut that won't come loose, torque to 180 ft-lbs with a 1 5/16 socket & you shouldn't have to worry about it again. If it was just me in the car, I wouldn't be posting : but with the car seat, well, it got my attention.

Good info. I find mine a bit loose frome time to time.

Maybe time to install one of those boostwerks braces?

The XJ I've built in my head has the boostwerks brace, HD Offroad shackle boxes, FT 3.5" long arm kit & a front D44 center section.
The one I can afford has none of that stuff.
The Boostwerks brace might be the answer for some folks. For me, I've got a locking nut (actually bought from McMaster) on the way.

I was actually just tightening mine an hr ago and was thinking the same thing. I have a steering box brace (not the boostwerks one) and am torquing it down at least once a month... I changed the nut and washer when I put a new box in a lil over a month ago and it still comes loose. Im gonna swing by Fastenal in the morning to see what I can find. Oh and no my steering box doesnt leak (yet). LoL

fastenal seems to have some legit grade 9 ones. 13$ a pop though so very pricey. they also have the regular ones we use for 1$ each. I Might order a bunch of those for trail spares. https://www.fastenal.com/web/products/details/38088

Well, post up your results after install.

Resurrecting this thread.
First, What did you guys end up doing & did it work?

Here are a couple of ideas I have on the subject
Why not use a standard nut withe a heavy washer & loctite 243 (oil resistant medium strength), torque to spec & forget it.
How about using an all metal lock nut (would one of the grade "C" bolts be strong enough)
Or use both standard loctited nut + a metal lock on top for extra piece of mind!

Leaking power steering boxes should be resealed. Otherwise, how is a rust bond going to form to keep that nut tight? ;-) There are other options to Loctite such as Vibratite. It's non hardening and oil resistant.

Torque that mofo down

I'd forgotten about this one.
I found that a standard height locking nut was too high - the locking portion of the nut extended past the threads.
About the best you'll get for this application is to clean the threads and use blue (not red, definitely not green) loctite on the nut.
You could use two nuts and it may help but to properly "lock" the first nut, the second has to be at full torque spec - and best of luck getting the ungodly amount of torque that a 7/8 thread requires for that. I guess a big damn breaker would get you there but I'd be hesitant to apply that force to the steering shaft, myself.
I don't remember what I wound up doing to the XJ. I sold it to my brother in law shortly after I got tired of the "fix and modify all the things" mentality that seemed to accompany the XJ. Bought a WJ with 4.7 and I'm happy with it, though I do miss the ole' girl from time to time.

I use loctite blue 'surface insensitive' on the KOH car and have never had a problem.

http://www.amazon.com/Permatex-24300-Surface-Insensitive-Threadlocker/dp/B000HBM5TQ

I use a lot of it. I remove the nut, clean the threads and retorque it with fresh loctite every season. When I do, I find it still tight every time.

I cleaned the nut & threads really well with brake cleaner then applied a heavy dose of oil resistant blue loctite 243
https://www.amazon.com/gp/product/B004L439FE/ref=ya_st_dp_summary
Torqued it gundatite & hopefully it will last, I marked it withe yellow marking paint & I'll keep & eye on it to see if it moves.