The Stovebolt Site Forums The Shop Area Driveline Steering Box Lubricant

I didn't want to hijack Roads Scholar's thread but this is related to his.

I have no problems with my steering. It doesn't jump around, there's no slack it it so I'm probably just poking a hornet's nest here. Anyway, I decided to look inside and it's packed with thick reddish brown grease.

Jon G suggest a 50/50 mix of Corn Head grease and 90w mineral oil in order for it to reach all areas of the gear itself.

I'm not removing the gear or rebuilding it. There's really no way to get all the thick grease out without disassembly.

What I was wondering is if it would make sense to add 90w mineral oil to the box and hope that the action of steering operation would mix the grease and oil together inside.

Or, should I leave well enough alone and forget about it?

That's a very good question, Otto. I can see where adding the Mineral oil could loosen up the grease that's in there but I'm also thinking about it creating a leak at the seal on the shaft. I "overhauled" my gear box by installing new bushings and a new seal and then filled with cornhead grease. My initial issue was play in the output shaft ( a lot ! ). If you end up going with the oil added, let us know how it turned out if you would.

Otto - I did what you are describing and it promptly ran out my pitman seal. Bright side, found and eliminated one more leak.

Once I replaced the seal, I did the 00 cotton picker grease.

Steering works, no leaks. I should probably just leave whatever kind of grease is in there alone. No need to open another can of worms.

Sounds like a plan. Don't like worms.....unless they are on a hook.

As I believe I mentioned before I am only speaking for the AD trucks...and I will admit I only have only spent 62 years fiddling with them. You folks can use corn head grease if you wish. Undiluted it is not correct and not what was meant for the AD steering gear and there is explanation of that by GM. If GM wanted you to use a thick grease, they would have not put a pour-in plug at the top...that much should be easily understood. And they would not have written this in the Shop Manual:

"The steering gear is filled at the factory with a special all-season gear lubricant. Seasonal change of this lubricant is unnecessary and the housing should not be drained. Whenever required, additions should be made using a lubricant which, at low temperatures is fluid and will not "channel" or cause "hard steering" and which will provide satisfactory lubrication under extreme summer conditions."

GM goes on to explain the pipe plug is positioned so as to prevent over-lubricating and that you should never use a pressure gun to force lubricant in the unit.

It is a design issue...the engineers had reasons for wanting it this way. If anybody in the audience is pouring corn head grease out of a grease tube into that hole, please take a video of it. I would really enjoy seeing it happen. Below are a couple of images of corn head grease. It is packaged in a grease gun tube for a reason.

The thing with thick grease is, it gets pushed out of the way and doesn't return. You could very well have a box full of grease and still have the gear teeth going metal on metal, and it's even worse if the gear box has a line of roller ball that run on the worm shaft.

If you pull the side cover off the gear box and carefully dig out what you can, you can make room for room gear oil. You then can reinstall the cover without changing the adjustments. At most you might have to cut a new gasket. Add some gear oil and work the steering back and forth. Your reddish brown grease is likely contaminated with rust, giving it the reddish brown color. At the lowest point in the gear box is the lower worm shaft bearing, most were barrel shaped and hard to come by, this is where water sets. I had to throw away two worm shafts before I found a good one due to crappy rusty grease.

I agree with you , Jon. I'm just wondering what I should do in my particular case. The grease inside my steering gear has been in it for more than 25 years at least.

I'm experiencing no problems with the steering but I got curious and removed the fill cap yesterday and discovered that the contents are more grease-like than oil-like.

I'm not going to remove the gear box so whatever is in there is probably going to stay in there.

Jon, would you recommend adding 90w mineral oil to the box? Would that accomplish anything?

I'll see if I can get a close up picture of the grease in the hole.

.

While we're at it, what lubricant is used in the shift linkage just up the shaft from the steering gear?

I would be hesitant to think 90 weight would combine well (or thoroughly to be exact) with the thicker grease (whatever that grease may be). Joe might have thoughts about this and we should see what they are. In an ideal world I would remove the box, clean it well and inspect things while I did that and replace the pitman shaft seal and gaskets, use thread sealer on everything else and re-adjust it. In a moment I'll mention something else about that.

As for the grease being brown...If somebody used the old style of wheel bearing grease in there or even the old style of chassis grease, it was naturally brown, got darker and thicker with age and it may have been sort of reddish in color. I have a couple of cans of the wheel bearing grease left here by the way. One is 50+ years old. We're having trouble with images it seems but later I could post some images of that grease so you could see it. It very well might mimic grease mixed with rust...especially one of the cans. This is what is called long fiber grease and not at all good for a steering gear. Some of that stuff actually looks and feels like somebody mixed hair in with it.

I don't mean to come down too hard on using corn head grease. A lot of people here seem to have convinced themselves it is the answer. Herd mentality isn't always correct as we all have learned but it can be compelling.

I was thinking while having a cup of tea and I don't have any idea how many steering boxes I've seen. Over 20 easily. A few of them simply could not be used because somebody had used the wrong grease or too little lubricant in them and some had harbored water (very bad). And we can't un-scramble that egg. No way to know what somebody did long ago. The wear on the sector gear of one was literally the stuff of highway nightmares. I'm not sure how anyone drove it in anything resembling a straight line. No adjustment was left at all so the wheels would just pick their own path.

If you do take out the steering box and make a project out of re-doing it, please automatically replace the pitman bushing and check the shims on the adjustment side. Because the pitman shaft/sector gear is predominately limited to partial motion under stress, that bushing wears out in an egg-shape and that in my experience makes it harder to seal that area. You know, the lubricant runs toward the bottom/top as you'd expect it would and the more it wears the more the shaft bounces up/down and leaks. The balls don't always require replacement and the top and bottom worm bearings are often pretty much okay with adjustment but I'd look at them to be sure. I hate to say it but those bearings in worn condition might be better than the offshore made ones you find today. Once you remove the sector gear just turning the worm shaft a bit can reveal a lot.

The shift linkage? There was a Lubriplate grease I always used. Can't recall the name of it offhand but it stayed put and did a good job.

Thanks for your input on the gear box. I think I'm just going to have to leave it alone for now. The truck steers too well. I installed shocks, wheels and tires 5 years ago and never had it aligned. I can let go of the wheel on the highway and the truck tracks perfectly straight. Tire wear is perfectly even across the tread. It's actually quite amazing.

There's no unusual behavior with the steering over rough roads , either so I'm virtually certain there is nop water or rust in the steering box. Eventually I may remove the gear and do all that you say but right now I don't need to do elective surgery on any of these wrecks. I have enough to do on them with actual problems.

I posted on the other steering box lubricant thread that I am planning to try the Tractor Supply Super S 1 quart #00 Cotton Picker Spindle Grease, seems like it has similar qualities as the original GM product.
Comments, suggestions?

Thanks,
Glen

Did you read the whole thread? Mix it with 90w mineral oil that Tractor Supply also sells.

Not saying it’s “right,” just first hand observation point on the 00 cotton picker grease….

It comes in a squeeze-type bottle much like the 90w or 80w-90 gear lube we all know. I would consider those types of lubes to fall very much into a “liquid” category.

It flows out nicely and seems to self level rather easily. But it’s somewhere between “liquid” like those gear oils and “grease” like axle/bearing grease. A bit closer to the liquid end of that spectrum.

Hard to describe. Room temp butter if it was a pretty warm room? Jello that hasn’t quite set up?

FWIW- I don’t see how it could possibly channel and leave voids as some thicker greases might.

The spindle grease/lubricant is much closer by far and it might be just fine. 00 will be notably more fluid than 0 grease. 0 is what I might compare to yogurt or maybe mayonnaise. Sour cream? The one thing I like about the corn head grease is it does have extra additives for friction protection. I'm not sure about what the cotton picker lube has...cotton picking is a whole lot different from corn picking. More bolls to gather, goes faster, very little weight, much lighter stems, etc so there's that. Probably just between the two would be an ideal spot.

I just posted on the other thread, corn head is made from one type of base, cotton picker is a different type of base. They use the cotton picker base because it's easy to wash out of the cotton at the mills. Cotten spindles run faster so a thinner base is needed, but both are semi liquid greases that flow under a load, and settle when parked.

A steering box is not a rotating spindle or rotating gear box like what the greases are designed for. A steering box is not loaded down for extended periods of time, I doubt it has much load at all compared to what the greases being discussed are designed for. Corn head was brought up this site probably 20 years ago, thats when I switched mine over.

I'am in the category that any 0 or 00 grease that flows is better than gun grease or a liquid gear oil thats going to run out. The brake shop here in town thats been around since the 50's used gear oil and gun grease mixed about 50/50 for steering boxes, if it came back with a leak, they added more grease to slow it down. I was semi related to the owner till he passed away, his son now runs the shop.

Probably 50% of a steering box life is just holding the worn shaft straight, no real turning involved other than minor corrections. Mine is 86 years old with who knows how many different lubricants it has had, it still adjusted up to spec's and drive great, so I don't think the corn head grease is going to hurt it. My main concern is to have the bearings and roller balls covered in lubricant to keep from rusting, and being close to the exhaust pipe keeps it warm and probably flowing better.

With old who knows what type of grease, adding some liquid gear oil will help liquify what in it, so when the time comes to clean it out, it may actually flow out. Worst case is, the gears get some lubrication even if the old stuff is solidified.

I'm clearly not the expert here. This is the gear oil I'm running in my 53 3100 stock steering box. The box is totally rebuilt with EPAS Performance electric P/S and a Howe 1:1.5 steering quickener. I made a 15" wheel out of PC-7 epoxy and used the 59 wheel to get the turn signal mech.

I'll try again to post the images that would not post yesterday. Here is the corn head grease. It has stress and wear reducing additives and it was designed for one very specific application. And for that application it is very good. Before you go out and buy some I think you should see it. You can read the data sheets and all, learn about the nice additives it contains...but the consistency is not what GM engineers wanted. To me, that's the entire game. It is 0 grade, thicker than 00 (resembles chassis grease), is obviously not pourable and heat does not cause it to self-level. At least at 110 degrees it remains just what you see here. I've checked it. The other day I compared 0 grade to yogurt or maybe mayonnaise.

As I've said before, over the past 60 years I've seen several of these units. Some were okay and some were useless/dangerous and the most common reason for destruction/failure was the use of improper lubricant (in one case the grease had simply become a solidified tunnel shape and the worm, the ball nut and sector gear were bare---nothing in there could be used safely). I figured it had been run that way a long time. I screwed the adjustment down to the very end and it wobbled around at all points of use. Whatever you choose, good luck.

Thank you, Jon. I'm glad I asked the question, not only for my benefit but for everyone else's.

Yes it definitely is obvious that corn head Grease was not the intended viscosity for any lubrication in the steering gear. How would you even get it in without a zerk fitting?

Anyway, in my case I think the best course of action for the short-term would be to add the cotton picker spindle Grease, 00 lube to fill whatever voids maybe in the gear.

In the long term I'll add that to my list of projects on this truck and put it in a priority position over new seat covers and floor mats.

True the corn head is not going to flow out of the tube, but if you start stirring it up it liquify pretty quickly. The intended use was to solidify why setting still so it didn't leak out, but become liquid when being used.

I was able to push the tube contents into a zip-lock bag, cut off the corner, and simply squeeze it into the gear box.

If your seals are good, Cotten Picker, or gear oil will be a best option, but if it leaks now, corn head is the better option in my opinion. Watch the video, does it still look solid while running? John Deere Corn Head Grease

I see your point, Joe but how much movement and thus heat will be generated in a typical steering gear box on an ad truck? Most of the time you're not even turning the wheel.

Unless you're Auto crossing the vehicle at road Atlanta that gearbox isn't going to get much of a workout and I don't know if it could turn that corn head Grease into the liquid as shown in the video.

Maybe it liquefies just enough to flow down into the cracks and crevices where it's required and then stays there when it hardens up.

I currently don't have any leaks so when I add the cotton picker spindle lubricant maybe I'll see some. But I figure that's what I'll do and see what happens.

I'm sure another can of worms is about to be set loose

That corn head grease is what's called thixotropic, meaning it liquefies when agitated. It doesn't take any real heat for that to happen.
The mud in Cook Inlet near me does that, which is why people can slowly sink into it and get stuck. Tossing a rock in will create a small crater with the rock at the bottom. I once had to climb up a rock covered road cut that was coated with mud. As I stepped on it and agitated the mud, it suddenly slid off the slope. Really weird stuff.

Yes, exactly...I've said that here several times. Thixotropic is just what it is. But the mechanism of the corn header machine spins fast. Your steering gear does not.

Please look at the attached image. You might have to increase the size. The red arrow and the yellow line show where the maximum amount of lubricant can be poured before it starts dribbling out. The green arrow shows where your upper mast/worm bearing is. The box sits on your frame so the top of the pipe plug is just about right on level. This was designed so that when full with a self-leveling lubricant the lubricant would run into the top bearing and bathe it constantly...it will naturally seek that yellow line. You can also see in a correct environment the lubricant will run through the bearing, lubricate it all the way to the top and past that bearing into the mast about 1.5 inches so it will bathe the bearing from the back side also. That's it. Right there is the design the GM engineers wanted...and it is very clever. If you lose lubricant, that reservoir up in the mast means your top bearing should not run totally dry...at least until you've lost a lot of lubricant. And that's why they say to keep it topped up with a lubricant that is fluid even under cold conditions. The whole she-bang was designed with a specific and very well planned lubrication scheme. Hopefully you can see my image and hopefully this helps.

Thanks for all the posts and suggestions, information, and so on. My '38 steering box has no ball bearings, just bushings. I have tried 90W gear oil mixed with cornhead grease, I have tried just 90W gear oil, I have tried just cornhead grease. The problem seeems to be when the box gets hot from the exhaust pipe heat the lubricant thins out and leaks out the side cover plate, I am using the new type seal on the pittman shaft and that does not leak. Years ago I used the cork seal there and the 90W leaked out there too; so now one leak fixed but still working on the other one. So I'll give it another shot and clean out the cornhead grease and use the gear oil resistant sealer for the side cover plate.
Thanks everyone,
Glen

Glen, we took you a long way around your issue but hopefully we all learned something on the way.