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No, the axle nut is a 6 point 36mm.

The hub bolts use a 12 point 13mm.
 

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Yah - that "12-point" dingus is a retainer cap (why they couldn't just use a castellated nut, I don't know...)

Remove cotter, remove retainer, remove nut. Service bearing/shaft/whatever you're doing. Reinstall nut - torque to, I believe, 175 pound-feet (spec's on my site under Tech Archives, link in sig. All specs taken from FSMs. I just don't have all FSMs. Yet...) If your torque wrench doesn't go to 175 pound-feet, you can use never-seez on the nut threads and reduce that specified torque value by half - 87-88 pound-feet. Your torque wrench should be able to handle that neatly.

Install retainer. If the slots won't line up, tighten the nut slightly until they will. Replace cotter pin with new - never reuse a cotter pin!
 

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Yah - that "12-point" dingus is a retainer cap (why they couldn't just use a castellated nut, I don't know...)

Remove cotter, remove retainer, remove nut. Service bearing/shaft/whatever you're doing. Reinstall nut - torque to, I believe, 175 pound-feet (spec's on my site under Tech Archives, link in sig. All specs taken from FSMs. I just don't have all FSMs. Yet...) If your torque wrench doesn't go to 175 pound-feet, you can use never-seez on the nut threads and reduce that specified torque value by half - 87-88 pound-feet. Your torque wrench should be able to handle that neatly.

Install retainer. If the slots won't line up, tighten the nut slightly until they will. Replace cotter pin with new - never reuse a cotter pin!
Oh yup that's what i was thinking of.

Yes you were correct 175 ft-lbs.

And what's the reasoning behind reducing the value by half if your torque wrench doesn't go up to 175?
 

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Oh yup that's what i was thinking of.

Yes you were correct 175 ft-lbs.

And what's the reasoning behind reducing the value by half if your torque wrench doesn't go up to 175?
Torque specifications given in service manuals are for "clean, dry" threads unless otherwise specified.

That "clean, dry" value is to be modified for the following lubricants -

100% of total for threadlocker compounds.
95% of total for Room Temperature Vulcanising (RTV) "silicone" sealants.
90% of total for PTFE-based thread sealers (preferred to use paste, vice tape.)
67% of total for clean engine oil or chassis grease.
50% of total for anti-seize compounds.

This is done to reflect the lubrication afforded by the various compounds. While you're using a torque wrench to stop at a specific applied torque (turning force,) what you are actually setting is the "preload tension" of the fastened joint - or the clamping force provided by the screw.

You start with the "clean, dry" specification - anything that changes the friction of the threads against each other changes the final preload - dirty or corroded threads will require more torque applied to get to the desired preload, while lubricated threads will require less torque applied to get to the same preload value.

Think of a screw thread as an inclined plane ("ramp" in common terms.) You're pushing, say, a 200# load up a ramp. It's going to take a fair amount of force to move, right? Make the bottom of the load rough, or make the ramp surface rough, and it's going to take more force.

Alternatively, coat the ramp with oil (assume you will have the same traction under your feet.) The load will suddenly be easier to move up the ramp, no?

Same principle applies here. Due to the extreme lubricity of the never-seez, you are reducing the torque by half - in this case, since you have to apply so much preload, you run the risk of overloading the bearings and either brinnelling the races (due to the extra added pressure - particularly when static) or of simply wearing out the rollers (because they're being squeezed between the races too hard. Bearings require a certain amount of preload to work with maximum longevity - too much or too little can lead to premature failure.)

In fact, in cases like this (wheel/spindle bearings,) I've noted an increase in bearing life when lubricating the threads and using a reduced torque value, principally because you are able to preload the bearings more consistently than you would with "clean, dry" threads.

The basic idea here is, if your torque wrench doesn't support measurement of 175 pound-feet of applied torque (most hobbyists won't have one,) you can get the preload value down into the range of your torque wrench by cleaning and lubricating the threads - engine oil or chassis grease brings it down to ~117 pound-feet, and never-seez brings it down to 87-88 pound-feet - both of which should be well within the range of hobbyist's tools. The use of lubricant carries an added advantage - it makes the thing easier to take to bits next time. I also tend to use never-seez on the unit bearing retainer screws - then torque them to 37-38 pound-feet, vice the "clean, dry" spec of 75 pound-feet (so I can take those damned things off later if I need to as well!)

Remember, if the FSM value doesn't list a lubricant as required, it's a "clean, dry" spec. There are two fasteners I can think of offhand that want to be lubricated - the crankshaft nose screw (1/2"-20, 80 pound-feet lubricated with clean engine oil) and the driver's side front cylinder head screw (1/2"-13, 100 pound-feet with PTFE paste, plumber's pipe dope, or similar thread sealing compound. Not a threadlocker.)

Make sense now? Or have I only succeeded in muddying the waters further?
 

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Just wanted to add... when you remove that retainer (after you remove the cotter pin), you'll see a "wave" washer. This is not broken or defective, it's how it's supposed to be. You'll want to make sure to reuse that wave washer and not replace it with a regular one.
 

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Discussion Starter #13
thanks guys... I just needed the nut size I have done this before but it has not been for 5 or 6 years... but the hole refresure cours was great...
5-90 Man you know your stuff and I have to say most people say I go into way to much detal when explaning things...lol I think I have found a new Friend.........:cheers: and thanks for the info guys..... this should be all in a thread to be kept for others to use.....Keyl
 

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Wow thanks for putting the effort into that long explanation 5-90; I notice most of your posts at NAXJA are the same way. Yes it does make complete sense now.

But I gotta ask - where are you getting this information from? Are you a mechanical engineer?
 

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Anytime guys - I like to teach! That's why I'm writing books now.

I figure since I can't manage to work for anyone else anymore, I need to find something productive to do - so I write. And, hopefully, it will sell. One book out, working on two more, and at least one more planned...
 

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I highly recommend using a 6-point 36MM socket, not a 12-point. That is one nut you don't want to gamble with stripping.
I highly recommend using a 6-point 36MM socket, not a 12-point. That is one nut you don't want to gamble with stripping.
36mm leaves way too much play, 1 3/8" fit perfectly, I read tons of forum saying "highly recommend 36mm"..........no, 36mm is too big unless jeep decided to use a different size just on mine
 

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Wow, dead thread resurrection. Somehow I remember skating by with a 36mm, but remember it being sloppy. I was borrowing a socket back then, and my choices were really limited. I have no idea if it changed over the years or what, but I agree, 36 was wrong. I love 5-90 and his info, he can be a walking encyclopedia, but by his count I think much of my stuff is twice as tight as it should be. Its not though, as my hubs operate fine and spin correctly. Certainly an eyeopener and something to watch for.
 
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