M38 - Nothing at all to do with M151s

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Re: M38 - Nothing at all to do with M151s

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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 20th, 2017, 8:44 pm

Had to take a day away from the project and get some housework done. It's good to step away from these kinds of things from time to time. You come back with a fresh perspective and the laundry done!

Time to remove the spindle. As I remarked earlier, at this point it's presently only held on there with a very slight interference fit between the machined surfaces. Either thread a nut on the end of the spindle to protect the threads or wrap a rag around it because when it comes off, it comes off all at once and down she goes. Using a hammer or something softer than the spindle, tap on one side, fill the gap you've created with something wedge-like, like a large flat screw driver and then tap on the opposite side and out it comes.

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Note the gold-tone coloration on the inside of the spindle. That's a guide bushing and probably bronze. It has two very clever relieved areas cut into its face with likely has something to do with picking up lubrication.

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Cooper sez, "Good job, Daddy-O!"

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And, it's back to watching the world go by... A dog's life is a simple one.

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Mmmm! Eau d' 90 weight! Smells good!

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Next, tie rod ends. Loosen the castellated (or castle) nut.

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Get set up for giving that knuckle a good shock by putting one hammer against it on one side and then whack it on the opposite side.

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If it doesn't drop right out, flip the castle nut over, thread it on the full thickness of the nut to protect the threads of the tie rod end and rap it squarely with a copper mallet.

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And out she comes!

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Flip the nut back over, put it back on and throw that old cotter pin back in as a gentle reminder for reassembly.

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While I was there, I couldn't help but notice the awesome quality of this ground at the battery tray. Nice, huh? But this is a big trap for those of you who may be new to all of this. When you are working on a vehicle like this; one that needs at least one of everything, if you are paying attention, you are going to notice lots of things like this. Things that desperately need attention. But, in order to remain persistently organized, jumping from one part of the project to another isn't going to cut it. That's buckshot mechanics and it's a no-no. Poor grounds have absolutely nothing to do with what we're presently about, so, the thing to do is make note of it and come back to it and by "make note of it" I don't necessarily mean making an actual note. Notes get lost, even when they're on bloody huge pieces of cardboard. Writing on the vehicle in chalk or with grease pencil isn't permanent either. I like to use neon colored zip ties specifically for this purpose. Slap one on what you want to come back to and go right back to what you're doing.

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Brakes are part of this iteration and this zip tie is keeping this junk out of my way until I'm ready to deal with it. I love zip ties and I buy em by the gross! Speaking of gross, I *ahem* believe my rust hole is showing! :roll:

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With the spindles removed, out come the axles. Remove them carefully and, as a whole, like you'd deliver a baby. These are Bendix style joints. But...pull the axle out by one end and there is a possibility that you'll suddenly find about 4 large silver marbles suddenly rolling around at your feet! If this happens don't lose your mind. Just keep everything kind of together and when it comes time to reassemble, mic' them and the ones that are closest in size go in opposite one another. Easy-peasy. It's 1940's technology, not rocket science.

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Here, I've wiped one shaft off. Notice how the grease has migrated past the seal and into the "wet side" of the axle? That's a clear indication of a bad seal.

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And now we've made two big gaping holes.

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Next we'll remove the guards for the brake lines. They are bolted to the top of the upper king pin bearing cap. We need to get these out of the way so we can remove the seals at the rear of the steering knuckle.

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The guards are the same part, used on both sides. They are held on with only two of the four bolts securing each of the upper king pins.

Author's note - The two bolts holding each guard on are supposed to be just a tiny bit longer than the other two bolts. Vehicles this age have most likely had some work done in this area and there is a very high likelihood that these longer bolts have found their way into another hole reserved for the shorter bolts. If that happens, there ABSOLUTELY WILL BE DAMAGE to the king pin bearing, so pay close attention when removing these.

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This one appears to have had a close encounter of some kind..

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With those removed, we'll move on to the grease seals at the back side of the knuckle. These grease seals have an upper and a lower hemisphere. Each half is held on with four short bolts. Your new grease seal may be one solid ring.

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This is why we do it, folks.

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Note the large gap that the grease seal has to cover when the steering is hard over.
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And here I've found a tiny little nugget of goodness amidst all this awful stuff. VERY cool! I'll make sure that finds its way back on when we put everything back together.

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Ok, here is where I had to put the camera down because this is where I got really dirty and greasy. Order of disassembly was as follows - Loosen all the bolts securing each of the king pin bearing caps to the steering knuckles. Do not remove any king pin bearing cap until you have loosened all the bolts. If you do and if you then starting working on loosening other bolts on the opposite end, things get really wonky. It's not a fatal mistake but it's very awkward and people will make fun of you behind your back and call you names. Next, remove the upper and lower king bearing caps, straight up and straight down. Look for and recover the shims that are sandwiched between the top king pin bearing cap and the steering knuckle. Keep them all together, where they belong, for now. The shims are for setting the proper preload on the bearings. Then, pull the knuckles straight off the end of the axle tube. The lower bearing will, most likely, fall out of it's cup. No worries, they're surprisingly tiny and a short fall won't hurt it a bit. With that you're ready to start wiping up and disposing of lots and lots of really horrible grease...

...and with that done, this is what you'll end up with.

The bearing cups are going bye-bye. Actually, they went bye-bye a long time ago. This damage, even and localized is called false brinelling. Consider that these bearings don't go round and round like the bearings of an axle. True brinelling takes place while the bearing is in motion and thus, leaves a wear pattern at an angle. These bearings probably spend their entire life within only several degrees of their initial installation point which makes it all the more important that they be adequately packed with lubricant and that the preload be set properly. The cause of this damage is simply vibration between the roller bearing and the cup while the bearing is stationary, relative to the cup. Every bearing cup on the front end has this wear and will need to be replaced, along with the bearings.

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Here I have laid out my parts in a sensible manner, prior to the laborious process of cleaning.

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This seal actually came out intact! :D The other side...in a million little pieces. :shock:

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Inner bushing.

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Here, I'm having a go with the wire wheel. This did a very fine job inasmuch as I removed most of the dirt and surface rust. But, I'm afraid the whole thing is going to need a bit of a polish with crocus cloth and maybe a wipe down with Ospho to kill the rust deep in the pores of the metal. The new seals will require a relatively smooth surface to work against. If you find you have some really deep pitting in this area it must be filled and brought back to smooth surface.

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And finally, more stupidity. Where the heck did that zerk go?

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Last edited by m3a1 on October 29th, 2017, 10:48 am, edited 9 times in total.
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 21st, 2017, 1:13 pm

Well, the little bits and pieces are piling up so I decided to try to firm up the to-do list. Since my son is back in school, his interest in rolling up his sleeves and getting dirty has been waning a bit.

So, I did a little prep for this oil filter can's trip to the blast cabinet and immediately launched into yet another WTF moment. I'm toying with the idea of replacing this altogether. Not that it doesn't work, or that it couldn't be made more presentable but I'd be spending a lot of time on this to sort it out. Who knows? Maybe a nice replacement with all the stickers would make a good birthday present for someone. I think that'll depend more or less upon a certain someone pitching in. :wink:

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And then I fell right back into this, since popping the bearing cups out is a snap. First, you get a socket that's the perfect size....

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...and then something to take the hit from the hammer...

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...and out they come!

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Here are all four bearing cups. They'll go on the pile, with their bearings, to become yard art or some other curiosity. What? Just throw them away, you say? Nah. I never throw anything away.

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All the bearings are shot. Here are a couple of bearings that are especially FUBAR. I've got the distinct feeling these were salvaged off something else and swapped into this truck already damaged. I've looked (which is one of the reasons why I cleaned up the knuckles today) and I just cannot fathom how these got this fouled up in this application.

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Then I spent far too much time sorting these out; degreasing, wire-wheeling, chasing the threads out, more degreasing, cleaning up the mating surfaces. I was going to blast these but I'm feeling this is good enough, considering the environment they live in. So, one more degrease and a good wash and then into primer and paint. The big plugs are filler plugs for grease and as you probably already saw, there's room for a LOT of grease in there.

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Finally, many many parts ordered today. O'Reilly's beat everybody's price on the bearings and cups but fell behind on the little odds and ends. Still plenty of clean-up to be done in the mean time.

Cheers,
TJ
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Re: M38 - Nothing at all to do with M151s

Postby rickf » September 21st, 2017, 6:50 pm

I had a sneaky suspicion this was going to become YOUR project, You just can't back away from it. :lol:
1964 M151A1
1984 M1008
1967 M416
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12/1952 M100- Departed
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Re: M38 - Nothing at all to do with M151s

Postby SturmTyger380 » September 22nd, 2017, 8:30 am

Hi TJ,

Does your M38 still have the stand for the battery box on the frame in the engine compartment? Mine is missing. It is long gone from some guy converting to 12 volts years ago and they torched it off.

I need to know the dimensions of the stand. I need to know the length, width and how high the level ledge stands above the frame and some help figuring the location to weld a replacement onto the frame.

Cheers, Alan
45' MB, ??' MBT, 47' CJ2A, 48' CJ2A,
51' M38 #1, 51' M38 #2, 51' M100,
52' M37, ??' M101A1 (1st Gulf War Vet),
53' M38A1, 53' M211, 65' M151A1, 67' M416,
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 22nd, 2017, 12:24 pm

PM to Sturm'
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 23rd, 2017, 3:59 pm

So, as was pointed out to me by a more learned member, and as you can see here, we have verified the cause of the damage to the king pin bearings. As it turns out, there are four longer bolts (3/8 - 24) that are meant to be used to secure the cages to the top of the bearing cap. Each cage requires (two longer bolts x two sides = four longer bolts). Because the metal of the cage is rather thick, they employed longer bolts. If this is something you weren't aware of (like me :roll: ) it would be very easy to simply assume they were all the same and just put them back in where-ever, because these aren't much more than about 3/16" longer than the others and with a glob of grease on the end, who would know?

And - since there are four assemblies, each requiring four bolts total and since there are precisely four longer bolts, it is a mathematical certainty that if even one long bolt goes astray, there will be a damaged bearing. Apologies in advance to you die-hard Willys guys, but that's just a lousy design.

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Here are the cages with the damaged one now straightened. Those are the old shims in the upper left of the picture. Since we are installing new bearings and cups, both sides must be reshimmed from square one. We cannot rely upon the values of the old shims to be correct with new hardware we'll be installing.

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An interior view of the uppers, assembled properly but without shims. As you can see, if a longer bolt finds its way into the wrong spot, damage is assured.

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Here is my son, whittling grime off the bearing caps before cleaning them up on the wire wheel

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And here is something you don't see every day. Stretched bolts! That's right, they start out being 3/8 - 24 and end up being approximately 3/8 - 16! That's WAY up there on the weird scale.

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Re: M38 - Nothing at all to do with M151s

Postby rickf » September 23rd, 2017, 4:23 pm

That is WAY up there on the stretch scale! Like about 1/32 before broken! They were probably quality American bolts for sure. And grade 5 , not 8. There is a reason grade 8 is not used everywhere. In that first picture it looks like one of the bolt in the one on the right is a coarse thread bolt, it would not have been stretched that far down in the hole.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 23rd, 2017, 5:37 pm

As always, your powers of perception amaze, Rick. In the first picture that is indeed, a coarse thread bolt!
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 24th, 2017, 8:56 pm

So, not a lot to report but an interesting thing came up. We had some weather come through so instead of wrenching I did some homework on this king pin bearing cap fastener issue.

I finally found detailed reference to it mentioned in TM9-8012, page 265, line (5) and page 266, line (6) but, the TM provides directions for using the LONGER bolt (1 5/8") for securing the king pin bearing cap and the SHORTER bolt (1 1/2") for securing the brake hose guard.

Simply put, the TM is WRONG. Now there's something you don't see every day!
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Re: M38 - Nothing at all to do with M151s

Postby rickf » September 25th, 2017, 8:11 am

One of the 151's TM's is wrong and gives the wrong float level setting and on top of that it was NEVER corrected until the next manual came out.
1964 M151A1
1984 M1008
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12/1952 M100- Departed
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 26th, 2017, 9:17 pm

Ok! So, the weather is taking a huge dump on us (but we need the rain) and there's not much we've been able to accomplish.

We did make a point of getting out between squalls and wiped down and degreased the front axles and disassembled them. Again, this is a greasy process so no pics of that. Sorry.

What I have here is the Bendix Universal Joint.

TM9-1804B, Page 100, provides a broad strokes review of this process. Here, we are not replacing any of the components; merely cleaning and inspecting.

Disassembly begins with removing the lock pin (AKA universal joint groove pin) from the transverse hole. (see photo below) Drift it out with a suitable punch and mallet. If one end is staked, drift it out from the OPPOSITE end (i.e. the staked end comes out first).

Removal of this pin will allow the hidden pin that retains the center ball (it is oriented on the long axis of the axle) to drop out of the ball and into the shortest shaft of your axle.

You can accomplish that by orienting the axle vertically, with the short shaft down, and bumping the lower end onto a block of wood or tapping upward on the end of the short shaft with a soft mallet. The specific placement of the center ball is what locates the four larger ball bearings so that the joint cannot come apart. It's a bit counterintuitive but it works.

Process of reassembly. Note that we have previously marked the components so that they don't get mixed up. 'S' is for the short axle shaft and both shafts of the short axle shaft were marked in this way. All the ball bearings, including the centering ball and pin, were kept with the axle shafts they came from because all these components wore in together as a unit and we plan on reusing them as a unit.

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The larger ball bearings were carefully measured and set up as a pair. Measure these on three axis. In this way you are also checking to see of the ball is out-of-round. Very slight variations in size will have very little effect, particularly on a worn joint but out-of-round balls are, or soon will be. a game changer requiring it be replaced. I did the same with the two smaller ball bearings, setting them up as a pair. More on this in a moment. The TM has some very specific information regarding these and it is worthy of review.

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Identify the sides of the joint that have the deepest wear. These are the sides that will receive the larger set of ball bearings.

On the issue of cleanliness of parts - Here we see the hole for the pin that secures the centering bearing in its final place. Despite the fact that the exterior of this component is quite clean, the cavity for this pin is quite deep and it still has quite a bit of old lube in it. It's depth is about half the length of a Q-Tip. Get it cleaned out completely because in a moment we are going to be putting that retaining pin in it. With the old grease that's in there it's going to hang up. We are looking for a good, clean, dry cavity for that pin to move freely in because in a moment we are going to rely upon gravity to make that pin fall into its final position. DON'T put lube or oil in there. Leave all your components completely dry.

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Pin is installed. You can see I have marked this component with a Sharpie so I can get keep it mated to the other half - 'S' means short shaft

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And now the pin has dropped into position. You can see it through the transverse hole for the Universal joint lock pin.

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Place the center ball over the pin and ensure that the hole in the ball, into which the pin will eventually rest, DOES NOT LINE UP WITH THE PIN, as seen here.

When the time comes to line it up you may find that it is difficult to determine how the center ball is oriented. It is perfectly ok to make a few identifying marks on the center ball with permanent marker to help you find it.

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Bring the other half of the axle shaft into position. It will rest upon the center ball.

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Prepare to insert the balls. If you are working alone it will probably be easier to bring the short end of the axle shaft back at an angle.

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Insert the appropriate ball bearings oriented, by size, to the previous wear on the knuckle; larger set of balls into the pockets with the deepest worn spots. Ensure that the two larger ball bearings are located diagonally across from one another and the two smaller ball bearings are located diagonally across from one another. The first three are easy. The fourth, a little more difficult. You will need to extend the joint's length just a little to get it in there.

With that accomplished, rotate the center ball so that its hole is in-line with the pin. Orient the axle so that gravity brings the pin down into the hole. If you have the center ball close, but not quite perfectly oriented, a gentle shake will generally help the pin find it's way into the hole.

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With the pin in place you will see that the transverse hole is now open again. Insert the lock pin and drift it into place. The TM calls for staking it to ensure that it doesn't work its way out. That's it!

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Coming soon....The Great Divide....over lubrication!
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Re: M38 - Nothing at all to do with M151s

Postby rickf » September 27th, 2017, 8:36 am

I remember the first time I did one of those. I learned a LOT of new words!!! Very well laid out TJ, you will save someone else from that fate. You need to put this tutorial over on the 503 in their M38 section.
1964 M151A1
1984 M1008
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12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
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Re: M38 - Nothing at all to do with M151s

Postby m3a1 » September 27th, 2017, 1:40 pm

So, while this thread really has nothing at all to do with M151s per se, you are going to notice some similarities in the manner in which we hash things out on these forums and you may be surprised how some people habitually cling to time-worn lines of thinking (that may just be wrong and leave us asking all the wrong questions), and the problems associated with 'Group Think' and the fascinating array of options that modern chemistry has presented us with, particularly in dealing with old trucks. So, here we go.

I title this - Steering Knuckle Lubrication - The Great Divide

The Tech Manuals for the M38 call for specific lubrication within the steering knuckle called, GAA , "Grease, Automotive and Artillery." This lubrication is introduced into the steering knuckle through a hole that is blocked off with a pipe plug, much like those we find on most differentials and manual transmissions. The reason for this is to allow you to see that you have a proper amount of lubricant in there. Just like your differential, the fill line is the bottom of the plug hole.

Well, what if I told you that GAA has given way to new types of lubrication and has become an anachronism? What if I told you that it is no longer being used by the military which has found something other than (and very likely better than) GAA to use? What if I told you that the people who have purchased these surpluses of GAA are charging an arm and a leg for it or quite often, will only sell it in bulk amounts. And, what if I told you that rigid adherence to the time-worn and erroneous idea that the information in the Tech Manuals was brought down from the mount by Moses (along with the ten commandments) is entirely the wrong way to think about things with the many options available to us? Two schools of thought - GAA is sacred stuff -or- GAA is not sacred stuff. Two schools of thought, hence our title The Great Divide.

Crusty old salts who, if they had their way, would have us still enjoying the company of our equine friends, give us their short answer, "Suck it up buttercup, go source some GAA grease, bust out your wallet, do what the book tells ya and tell yer mama I said hello." My response is, "Well, sorry Charlie, I've never been much of a joiner." In saying that, I'm left feeling like I'm left standing on the precipice of a great chasm, staring over at the other side where all the other happy little boys with their golden cans of GAA are standing and they, staring back at me, see me standing there with my tube of "other-than-GAA lube", while waiting for me to step forward and fall into the depths. It's a lonely, sometimes scary place..

This all began with something quite simple. If you have been following along, you have seen how the steering knuckle is assembled with the king pin bearings living in the same space with the axle's universal joint and thus, inevitably sharing the same lubrication, especially with the lower king pin bearing fully submerged. And yet, I was getting advice from old sages who were telling me to lubricate the king pin bearings with wheel bearing grease. Wait! WHAAAAT?!! What happened to the use-GAA-or-die-a-horrible-death thing?

Over the years, some of the original perspective on these assemblies has been lost to the sands of time. The old mechanics pack up their tools one last time and go home, and the new mechanics, when faced with old technology, go with what they know. Such as - a cone bearing must be "packed" and packing involves wheel bearing grease, which is thick, ergo - cone bearings all get wheel bearing grease. Eventually it becomes a sort of institutional group-think and I submit to you that George Patton Jr. put it best. "If everybody is thinking alike, then somebody isn't thinking!"

Now, they both may be cone-type bearings but they do entirely different jobs - wheel bearings are employed at relatively high speeds with 360 degrees of revolution on a vertical plane in a small space where they have only the lubrication they were packed with whereas, king pin bearings are employed at almost NO speed, in a large space where they enjoy almost constantly refreshed lubrication, and are moving only a few degrees at a time on a horizontal plane. They generally look the same and that's about where the similarity ends.

And the principle that a layperson should not blindly mix lubricants is sacred law. Ask any chemist. So I did! Three hours of hashing this out over the phone. THREE HOURS!

I happen to have a buddy, now retired, who spent his professional career as a chemist. Working for Uncle Sam, it was his job to make sure that military vehicles and all sorts of things associated with military vehicles were using the correct stuff. Some of that stuff had wheels and some of it had wings and some of it was so specific that using the wrong stuff meant having to send very expensive pieces back to the factory for re-coating or writing the parts off altogether.

So, I knew when I made the phone call, that his having over twenty years of saying, "Use only what the book tells you to use." would result in getting the suck-it-up-buttercup answer. Oh! I learned a lot about lubrication and a lot of it based on the chemistry of the stuff. Stuff that I felt I needed to know to make some informed decisions because I felt GAA was going to be out of reach for several very practical reasons, not the least of which was availability, not only roadside, but also in the long term. We also reaffirmed that mixing lubricants was still a no-no and could result in some rather serious consequences, particularly when mixing lubes actually degrades the lubricity (I LOVE that word because it sounds so dirty) to the point where it no longer lubricates. He presented that to me as what I would call "a dire warning", so if you do this, you do it at your peril.

But were we approaching the problem from the right direction? We weren't any closer to solving the problem than when I dialed his number. Were we asking the right question? Because sometimes, folks, it isn't always about Mil Spec. Sometimes it's better to work the problem from the civilian perspective.

So, after two hours of chatting, I finally challenged my chemist's standard answer with a simple statement of fact. The M38 has a civilian counterpart using the same front axle group - the CJ3A and, in fact, that axle group (with some minor changes) was used until something like 1971. They don't use GAA but you can bet they using something very similar! So, when I laid that on him....KaBOOM! (His head explodes) Stoney silence at his end of the line while he scooped his brains back into his skull. NOW, the answer was that it would then be okay to use an OEM-approved lubricant. And suddenly, HALLELUJAH!.... the clouds parted.

Luckily for you, dear reader, I am prepared to share with you the straight skinny.

In order for one to find a certified civilian counterpart to GAA, the only bonofide presented on greases that meet GAA specs are markings, either the NSN number for GAA (which changes depending upon the size of the container) or the Mil-PRF number for lubricants with the properties of GAA, and actually finding one on the shelves of most big name auto parts stores is...well, let's just say you'd have better luck finding a unicorn in your sock drawer under the Valentines Day card you forgot to give to your wife.. In short, forget it. Ain't gonna happen and let's face it, you aren't going to drive a hundred miles to a big manufacturer with a huge warehouse of lubricants and ask for two tubes of the stuff even if they did have it. Again...ain't gonna happen! How do I know? I spent hours and hours reading labels at many, many stores. Hours and hours of my life that I'll never get back.

So I asked another question of NAPA, O'Reilly's, Auto Zone and even the Jeep dealership. What was used back then? What was the OEM lube of choice? Nobody knew and the guys at Jeep, likely in an effort to save face (or perhaps with a more noble cause in mind, such as shooing the annoying old guy out of their dealership) waved a tube of very generic chassis grease under my nose and said, "This is IT!" (which was totally wrong) and frankly, none of them had even been around in 1971.

By this time I figured I was going to be completely on my own...it was sink or swim. So, what to use? Here are my parameters -
(1) I want to put the stuff in and forget about the whole affair...maybe forever...because it hurts my brain. :roll: I want what is an essentially fire-and-forget lubricant. Something that lasts longer and is better than just plain, everyday, run-of-the-mill grease. I want modern chemistry in my 1951 Jeep!
(2) Because of that, I want something that isn't prone to creating oxidization and other problems for the truck or for the next guy. That left out some very popular lubes which use some very popular chemistry and which, if you knew about it, would probably have many of you scrambling to change out your lubrication. (see line 1).
(3) And I want something that is typically on the shelves of most auto parts stores. If I need to do a roadside repair I want it to be available (which, naturally, totally rules out GAA).
(4) Because I am running an old truck with a good degree of wear and thus a good deal of slop in worn parts, I want a lubricant that resists squeezing out, has good adherence qualities but also has good flow (NLGI #2 - which is generally, the equivilent of peanut butter)
(4) I want something that is sticky and resists slinging but isn't sling-proof because the very first goal is to keep the axle's universal joint well lubricated ...but also to get some lubricant slung onto that top king pin bearing.
(5) And I want something that doesn't thin out when it gets hot. In fact, I want something that might even get thicker when it gets hot.
(6) I want something that is not hydroscopic or prone to washout.
(7) And I want something that meets or exceeds the performance requirements of the manufacturers of really darned expensive farm equipment. In short, I want it ALL

And parameter number 7 is what brings us back around, full circle to the topic of what questions to ask. Are we coming from the right place when we are looking for solutions? We started with Mil Spec, then on to general OEM automotive spec and now, to general OEM farm spec which I think you will quickly agree is a VERY good place to be!

Farm equipment generally has all sorts of things going on when they're in use. They sit for long periods of inactivity, they have high speed, low speed, no speed parts, they are operated with huge variations in temperatures and they are expected to perform under the worst conditions with the least amount of necessary maintenance. Hmmm...that kind of sounds like our old trucks, eh?

By now you're probably waiting to hear what I've selected as my steering knuckle lubricant. C'mon TJ! Let's have it! Well, you're going to have to wait for the big reveal. I think I have the stuff but, at the risk of another three hours of lecture, I have to run it by my chemist first.

Cheers,
TJ
Last edited by m3a1 on September 27th, 2017, 10:31 pm, edited 4 times in total.
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Re: M38 - Nothing at all to do with M151s

Postby fergrn37 » September 27th, 2017, 4:13 pm

You like the feel of the keyboard on you fingers, don't ya?
Some people are too busy knowing it all to ever learn anything
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Re: M38 - Nothing at all to do with M151s

Postby rickf » September 27th, 2017, 5:38 pm

Corn head lube.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone
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