NOS steering box or rebuild service

[Waller]

I've had my 2002 for 45 years and 340,000 miles. The steering box is loose, and has been adjusted many times.

 

I have two other used ones to try, but at this point I just want to buy the best solution I can find.

 

Is there anyone selling new or remanufactured steering boxes that are like new?

 

I'd rather spend a $1000 than scew around with testing each of the used boxes, or rebuilding any of mine. (unless there is a standard, well understood solution, like a bushing that always wears, as opposed to a worn worm and pinion)

 

I scoured the forums, but there is mostly conjecture. I see Ireland Engineering has a fast ratio, but I'd rather not increase steering effort.

 

Thanks for any help.

 

 

 

 

[Einspritz]

Pm me. I'll fill you in and you can decide.

[Rosso Pintura]

2 hours ago, Waller said:

(unless there is a standard, well understood solution, like a bushing that always wears, as opposed to a worn worm and pinion)

 

 

 

 

You may have seen this in a previous discussion, but the number one failure point of the box is the bushing in the top cover. The oil level drops over time, and the bushing stops getting the lubrication it needs and wears heavily. Screwing in the center shaft makes the worm gear push the center shaft off center, wearing the bushing, causing more play. So, the only real fix is to replace the bushing and keep the oil level up. Unfortunately, that bushing was never available separately, and ZF stopped making parts for that box long ago. You could make the bushing, but it is not as simple as it sounds. There is a oiling channel/notch cut in it which makes for even more fun to make. You'll have to decide how much time and effort you want to put into it.

[Waller]

That is super helpful, and the oil level in mine hasn't always been right up to the top (maybe 1 inch down). 

I did not find that in my search of the forums, which I thought was thorough. thank you, this is exactly what I hoped for, some specific knowlege of what goes wrong.

 

My brother runs a machine shop; If it can be made he can make it. I'll pull one of the spares apart tonight and have a look.

 

The other thing I havn't done is the idler arm bushings, they feel fine without having removed them; is wear at the idler arm easily observed without removal? 

Edited October 31, 2023 by Waller

[SplitDash]

What oil goes into the steering box?

 

[Waller]

According to the owner's manual, Branded 90 weight hypoid gear oil

[jimk]

1 hour ago, Waller said:

According to the owner's manual, Branded 90 weight hypoid gear oil

The owner's manual was written for what was availavble 50+ years ago.  A better choice from today's lubes would be one for a slow moving high load gear set, like that for a rock crawler application or a NLGI No 1 Semi-fluid grease.  There are steering box greases on the market rated NLGI No 1.  I use a SAE 290 gear lube for rock crawlers.

[JohnP_02]

I had mine professionally rebuilt, vapor honed case and pitman arm painted for about $350. The rebuild kit I think was only like $50. Nothing super fancy, but fully functional. 
 

Edited November 1, 2023 by JohnP_02

[Mike Self]

If your spare steering boxes don't have a gazillion miles on 'em, they probably don't need a lot of repair/replacement.  I "overhauled" the steering box on my '73 at 260k miles, primarily because it was leaking like a sieve.  Upon dismantling I found little or no wear on bushings, bearings and both worm and roller; all it needed were a couple of new seals--$8 at the local parts emporium.

 

And...I did a column on the whole process; PM me if you'd like a copy.

 

mike

[mac]

BOTH bearings are important, not just the one in the cap. 

Just hope the Roller and Worm Gear are undamaged.

Oh, and the Cap gasket isn't the easiest to source.  

 

JohnP_02:  You were lucky.  Your Roller and Worm had to be OK.  

 

Mac. 

[Mike Self]

4 hours ago, mac said:

Cap gasket isn't the easiest to source.  

That is a paper gasket--make one yourself from gasket paper.  Takes about five minutes with small scissors and a paper hole punch.

 

mike

[TobyB]

Firstly, as mac says, if the worm's galled, the steering box is pretty much done.

 

There were some replacements made a good while ago, and maybe a few in the

parts bins in the nether regions of crafty old shops, but by and large, 

there just aren't any to be had anywhere these days.  And no, you can't

3d print one.  But you're welcome to try it if you have to.

 

After that, it's repairable- if you can find someone to do it.

But honestly, if the worm is clean and it doesn't have play at the straight ahead

position, and the screw's not buried in the locknut, you'll be fine.

 

And yes, an extreme pressure fluid grease seems to be the answer.

Synthetic, if at all possible, just because of the higher lubricity.

 

t

knowitall

[mac]

6 hours ago, mac said:

BOTH bearings are important, not just the one in the cap. 

Just hope the Roller and Worm Gear are undamaged.

Oh, and the Cap gasket isn't the easiest to source.  

 

JohnP_02:  You were lucky.  Your Roller and Worm had to be OK.  

 

Mac. 

 

[AceAndrew]

@Furry Camel isn't wrong on this.

 

While yes, the roller and worm gear are important, they are less likely to have wear than the bushing in the top is.  However, moderate wear in that top bushing will be less catastrophic than a pitted roller/worm (which is DOA).  

 

Out of the dozens of steering boxes I've gone through, the worm/roller are good to use about 80%-ish of the time (California based, so those figures might differ in other climates).  The top bushing shows at least some wear in the majority of the boxes, but more often than not, it is at least usable as is.

[Buckeye]

Take apart spare ones that you have, evaluate bushings, worm/ roller surface conditions then decide. You can do it yourself  if you are wrenching or have someone do it for you.

I went through this process 2 weeks ago, parts were in good condition given this 48 years old steering box. Do not let 'pitman arm' removal horror stories scare you.