Steering Gear Lubricant

[Eric S]

On the steering gear (NON Power Steering), the 1956 manual asks for Multipurpose-Type Gear Lubricant, S.A.E. 90
I pulled the cover to see the condition inside and see there is an oil there.
IMG_20250929_145853_930.jpg
This is an oil, right? Could it be the same as the Gear Oil we use in gear boxes, axles, ...?

[jopizz]

Yes, it's the same as what's used in the rear axle.

John

[simplyconnected]

Gear oil is good but packed grease is better because it cannot leak out.

[Eric S]

Do you mean regular car grease or a mix of oil/grease maybe?

[simplyconnected]

Do you mean regular car grease or a mix of oil/grease maybe?

Ford sent out a Service Bulletin regarding this issue. The bottom line is, grease will not leak out, probably ever. Steering gears don't get much wear when lubricated. I guess if you want to use 90W with grease, it really doesn't matter, just don't thin the grease too much.

What kind of grease? I would use a moly/lithium grease. I perform a test by putting a dab of grease between my thumb and index finger. When I pull my fingers apart, does the grease 'string'? If so, it's for me. - Dave

[Eric S]

And of course nothing works by the book here.
I adjust the screw on top of the gear box. I have a hard point every half turn. I can pass it though.
Play at steering wheel decreased but if I continue for around 2 turns I don't feel much difference.
I don't seem to feel any difference in required force to turn the steering wheel.
I lifted the wheels off ground.
Is it just a matter to eliminate play at steering wheel and stop there?

[jopizz]

Once you eliminate the play in the steering wheel stop there. The adjuster is not a fix for a worn steering box.

John

[simplyconnected]

John is right. I've seen too many steering gears that were trashed because the owner tightened them. I know, this goes against our natural instinct but the Service Manual covers this adjustment. It requires a very light touch.

Just after I retrofit rack and opinion steering in our '55, I got a call from one of my restoration buddies. He needed my steering gear for a '56 Ford because he couldn't source one anywhere. This was all about owners who 'adjusted' their steering gear, and trashed it. - Dave

[pbf777]

Just a note:

The specified as "correct" lube is "gear-lube", not "grease"; but yes, if the seals are bad, it does have the tendency to leak out.

The problem with grease, and the reason it wasn't specified for this application is that these are relatively slow moving parts which don't generate a great sum of velocity for the "sling-off" or heat, both of which promote motion to the lubricant, therefore it tends to get pushed away from the critical working surfaces and often doesn't migrate back readily (this particularly of the "stringier" stuff), this as a gear lube fluid would. Note that part of the plan with grease function is that as the part generates heat, this from friction, the grease melts into a more fluid form, and then flows into the area of the event. Now it is the responsibility of the engineers to provide a reservoir or collection area in a proximity that would promote such, but this isn't as engineered or intended in the steering box.

Now, as leakage 'is' an issue with these older applications, and I realize that the O.E.M.'s often preferred standardization, I kinda wonder if "90W" really is/was the best choice, or rather was it just the best option of something that was already stipulated elsewhere in the chassis? So I've often utilized "600W Gear Oil" (popular with the Model A Ford guys), as being thicker it tends to "leak-out" less, but it's still a "gear oil" so it does still possess the capacity to flow.

The other option, if you are of a similar frame of mind, might be to create your own concoction of gear lube/oil (not "motor" oil) and grease as a thickener, mixed in proportions that make you happy; but just be aware that not all such mixes were ever intended, so your chemistry might not realize what you had hoped for in the end.

Scott.

[simplyconnected]

Just a note:

The specified as "correct" lube is "gear-lube", not "grease"; ...

That is old information that has been changed long ago. Here is a video showing grease:
Bing Videos
Bing Videos
Bing Videos

- Dave

[pbf777]

Perhaps . . . . .

But the old car still has the same "old" steering box in it.

As I was told, the "steering grease", as was later specified (in some applications) and possibly with the intentions of reducing loss through leakage and associated maintenance (manual said to inspect every 2000 mi.), was a special formula that was/is sometimes referred to as a "semi-grease", as it wasn't as thick, and definitely not "stringy" (simply stated, of shorter molecule strands in make up), so that it would not require as much heat for function and flow better at the lower operating temperatures of steering boxes.

But yes, if your steering box won't retain "fluid" for a reasonable period of time, and you don't want to have to keep "adding", not to mention putting up with the mess on the floor, then "grease" would be better than nothing, but I would recommend utilizing something in the way of reasonable for the application.

B.T.W. Did you happen to notice in each of the "Bing Videos" presented the steering boxes were empty? Did all the "grease" leak out?

[simplyconnected]

...B.T.W. Did you happen to notice in each of the "Bing Videos" presented the steering boxes were empty? Did all the "grease" leak out?

I have more videos but three examples are enough. I could not find ANY that recommended using gear lube in a Ford box. GM specifies, NLGI-1 type of grease but Ford does not:
Mobil Extreme Pressure Grease, Cartridge, 14 oz, Mobilux EP 1, NLGI 1, Lithium Thickener 121093 | Zoro
I use a good moly-lithium grease that does 'string'. The longer the string, the better, because that means the grease 'hangs on' to itself and to the parts inside. I'm not looking for 'high temperature' or 'waterproof' grease, I simply want lubrication.

How often do owners check the fluid level in their steering gear?
How come none of these examples changed their lower seal?
Where did their original fluid go?

For these reasons, Ford came out with a Service Bulletin that changed their specifications to use grease. After careful consideration and years of watching, I have to say, using grease is a good choice. Ford is not the only manufacturer that switched to grease.

BTW, this 'fix' costs very little. The alternative is to remove the pitman arm, then dig out the old seal, install a new seal, and finally, replace the pitman arm. Sounds easy? I had to add serious heat to one pitman arm I removed on a Willy's. Without heat, two heavy-duty pitman arm pullers broke. - Dave

[Eric S]

On my 1937 Douglas motorcycle's gear box, I use thixotropic grease. That's a grease that is (more) liquid when in movement but kind of solidifies at rest so it does not leak. It is a 85W90. Seems to be popular in old motorbikes.

I adjusted the gearbox just to reduce the play at the steering wheel as John & Dave advised.

[pbf777]

For those interested, providing an example and as an aid in the discussion of "NLGI" consistency numbers see:

https://en.wikipedia.org/wiki/NLGI_consistency_number

Here we can see that greases come in many different consistencies, but if we look at what is labeled as say "Normal" grease, it presents a consistency factor comparable to "peanut butter". This which doesn't readily "flow", that if not heated adequately, and therefore won't liquefy as intended, this providing a "changing-out" flow characteristic which provides new lubricant and carries heat away from the working surfaces, but rather may just be pushed aside, and remaining "out of the mix". And "clinging to itself" isn't a property that would be appreciated, rather just compounding the issue.

And as an example for further consideration when selecting lubricants, note that some of the steering boxes utilize rather small diameter "needle-roller bearings", this often on the sector shaft, and this type bearing doesn't do well with heavy greases as it causes them to "slide" rather than to "roll" and this isn't a good thing either.

Scott.

[Eric S]

I removed the cover on the steering gear box and pulled the adjusting screw. When looking at where the adjusting screw rest (round shiny spot) it looks as if the part is broken.
Just wondering...
IMG_20251011_143952_945.jpg