Pinion nut

[helirich]

I took a look under my truck before a long trip. While checking the driveshaft for loose u-joints, I noticed the pinion nut had backed off a little.

The right way to deal with this is to replace the nut and crush sleeve. But you have to remove the carrier to torque the nut correctly. I wasn't really in for a two+ hour job, so I just tightened it. Not much tech here but I highly recumend making one of these. It's just 1/2" by 2 1/2" flat bar with a couple holes.



It was allot better and I made my trip with no problem. I will fix it right later. Now for the question. Does anyone know if the crush sleeve work hardens? Although I got it tighter, it never got all the play out of the pinion. I was really reefing on it with a long cheater. Seemed like it just stopped.

[silent one]

I have replace a lot of pinion seals and never had a problem, no reason to change the crush sleeve unless there is another problem. The pinion is supposed to have some play in it, that's the backlash between the pinion and ring gear.


Sent from my iPhone using AutoGuide.com App

[Steve83]

Originally Posted by helirich

Does anyone know if the crush sleeve work hardens?

It doesn't. Work-hardening occurs within the elastic limit of certain materials. During work hardening, the unstressed shape doesn't change because the material springs back to its original shape when the stress is removed. Crushing goes beyond the elastic limit (by definition) into the plastic range. Plastic deformation destroys work hardening.

Originally Posted by helirich

I was really reefing on it with a long cheater.

How much torque? A new sleeve begins to crush somewhere above 200 lb-ft. An old one may crush slightly lower.

BTW
If your gears have worn enough to have some significant backlash, the pinion preload can be set with the carrier installed by only measuring the rotating torque within the backlash zone (no contact with the carrier/ring gear). OR, if the carrier & wheel bearings are well-worn, the effects of their drag will be minimal (by a factor of the gear ratio, plus a little for the gear teeth friction) on the pinion rotating torque.

[helirich]

Originally Posted by silent one

I have replace a lot of pinion seals and never had a problem, no reason to change the crush sleeve unless there is another problem. The pinion is supposed to have some play in it, that's the backlash between the pinion and ring gear.

This is not just twist play. It moves a little front and back.

Originally Posted by Steve83

How much torque? A new sleeve begins to crush somewhere above 200 lb-ft.

I would think more than that. I didnt use my torque wrench. (I dont think it goes that high)

Originally Posted by Steve83

BTW
If your gears have worn enough to have some significant backlash, the pinion preload can be set with the carrier installed by only measuring the rotating torque within the backlash zone (no contact with the carrier/ring gear). OR, if the carrier & wheel bearings are well-worn, the effects of their drag will be minimal (by a factor of the gear ratio, plus a little for the gear teeth friction) on the pinion rotating torque.

I guess that could work. When I set up the gears (about 10 years ago) I used a company torque wrench. My torque wrench doesnt go down to in/lbs. (for the preload, not the pinion nut) So i guess you could say My current tq wrench doesnt go high enough for the nut and doesnt go low enough for the preload. LOL

[Steve83]

No single torque wrench would. It takes a needle- or beam-style to check preload. Click & digital won't do it.

[helirich]

Originally Posted by Steve83

If your gears have worn enough to have some significant backlash, the pinion preload can be set with the carrier installed by only measuring the rotating torque within the backlash zone (no contact with the carrier/ring gear). OR, if the carrier & wheel bearings are well-worn, the effects of their drag will be minimal (by a factor of the gear ratio, plus a little for the gear teeth friction) on the pinion rotating torque.

Do you suppose I could jack up the rear and see how much torque it takes to turn it with no preload. (for example 10 in/lb.) Then tighten the nut till the preload goes to 25 in/lbs. Giving a preload of 15 in/lbs.

What I'm saying is torque cumulitive?

[Kingfish999]

if the pinion moves front and back then the bearing is bad. you really need to replace it and do the job right. doing it halfassed will jsut make it not reliable. my friend replaced his halfass and it blew up in less than a month

[Alvin in AZ]

Originally Posted by Kingfish999

if the pinion moves front and back then the bearing is bad.

http://www.youtube.com/watch?v=7MWsPJBCrww

----------------------------

Steve, where'd you get the crazy ideas plastic deformation -doesn't- work
harden steel and plastic deformation even removes(!) work hardening?

Alvin in AZ

[Kingfish999]

Originally Posted by Alvin in AZ

http://www.youtube.com/watch?v=7MWsPJBCrww


Alvin in AZ

holy crap. must not have any bearings or carrier in there for that

[helirich]

Alvin, thats pretty good, LOL. Mine was less than an 1/8". Now is less than 1/16". But it still is not preloaded.

[Alvin in AZ]

Originally Posted by helirich

Mine was less than an 1/8".
Now is less than 1/16".
But it still is not preloaded.

Cool, I've snugged 'em up before and had 'em last years and years. :)

The crush sleeve or solid spacer is the -minimum- size -before- any
bearing wear. ;)

Tightening it down ain't gonna hurt anything as long as you don't get
carried away, IM(limited)E.

King's friend's experience could be the opposite of mine or the same. ;)
His was just too shot to go much farther -any which away-? ;)

But x2 King's warning and advice to do it right tho, at least you can
save the housing and rebuild it better than new, ...if that's your thing?

Alvin in AZ
ps HellaRich, can't find my notes or wiring diagrams since the move
-in- and so I don't know the wire colors for the defrost-power to
window-power swap. Heck, I can't even find the thread it was in! :/
No kidding. LOL :)
pps- Having heard ol'guys talk about rebuilding rear axles and setting
up the gears since I was a kid... I fiNgure that torque readings on the
carrier and pinion preloads are mostly for -books-. YMMV on that.

[Steve83]

Originally Posted by helirich

...is torque cumulative?

Generally, yes. But with hypoid gears, it's not that simple. That's why no axle mfr. specifies preload torque with the carrier installed. The actual torque to turn the pinion becomes dependent on too many variables, including (but not limited to) gear mesh settings, oil viscosity, oil film thickness on the teeth actually in mesh (which changes with position & speed of rotation), oil temperature, carrier bearing preload/oil film... Will it get you closer than you are now? Probably. Will it be right? Probably not.

Originally Posted by Alvin in AZ

where'd you get the crazy ideas plastic deformation -doesn't- work harden steel and plastic deformation even removes(!) work hardening?

Mechanical Engineering 203 & 204, IIRC (Mechanics of Materials & Lab). BTW I wasn't referring to "creep", which is technically plastic deformation. But creep occurs in the elastic zone.

[Alvin in AZ]

Originally Posted by Steve83

Generally, yes. But with hypoid gears, it's not that simple. That's why no axle
mfr. specifies preload torque with the carrier installed. The actual torque to
turn the pinion becomes dependent on too many variables, including (but not
limited to) gear mesh settings, oil viscosity, oil film thickness on the teeth
actually in mesh (which changes with position & speed of rotation), oil
temperature, carrier bearing preload/oil film...

x2 :)

No carrier causing drag here...
http://www.youtube.com/watch?v=x5_0FYWgWI8
...and not much weight to keep it spinning either. :)

This one's ~3 minutes long...
http://www.youtube.com/watch?v=8APYO...ture=fvwp&NR=1

Mechanical Engineering 203 & 204, IIRC (Mechanics of Materials & Lab).
BTW I wasn't referring to "creep", which is technically plastic deformation.
But creep occurs in the elastic zone.

Cool! :)

Got my information from Metallurgy class, ASM's Metals Handbook and
silversmiths. ;)

Alvin in AZ

[helirich]

Originally Posted by Kingfish999

if the pinion moves front and back then the bearing is bad. you really need to replace it and do the job right. doing it halfassed will jsut make it not reliable. my friend replaced his halfass and it blew up in less than a month

I think most of the reason it moves is the nut backed off. When I tightened it back to the crush sleeve, it has very little movement. Of course it had none when i set it up ten years ago. So I guess there is some ware. I will check the diff oil for metal.

Originally Posted by Alvin in AZ

Cool, I've snugged 'em up before and had 'em last years and years.

I ve seen this too.

Originally Posted by Alvin in AZ

But x2 King's warning and advice to do it right tho, at least you can save the housing and rebuild it better than new, ...if that's your thing?

I have another housing in my garage. So if it packs it in, I will swap that one in. I would like to make a better truss than I have on this one.

Anyone following the pinion nut can disreguard the following.

Originally Posted by Alvin in AZ

Alvin in AZ
ps HellaRich, can't find my notes or wiring diagrams since the move
-in- and so I don't know the wire colors for the defrost-power to
window-power swap. Heck, I can't even find the thread it was in! :/
No kidding. LOL :)

I thought my Ipad wasnt posting. I guess it was the forum natzi's. LOL. Sometimes I think they are against the flow of information. In any case, I noticed that there was a fused lead for the defrost in the left rear fender. (behind the taillight) Is that where you are talking about? Does it make the rear window go faster? I know they can run the gate window by relays for an improvment. But thats alot of work.

Originally Posted by Alvin in AZ

pps- Having heard ol'guys talk about rebuilding rear axles and setting
up the gears since I was a kid... I fiNgure that torque readings on the
carrier and pinion preloads are mostly for -books-. YMMV on that.

I have set up several sets of gears. Its not too bad of a job.
What does YMMV stand for?

Originally Posted by Steve83

Generally, yes. But with hypoid gears, it's not that simple. That's why no axle mfr. specifies preload torque with the carrier installed. The actual torque to turn the pinion becomes dependent on too many variables, including (but not limited to) gear mesh settings, oil viscosity, oil film thickness on the teeth actually in mesh (which changes with position & speed of rotation), oil temperature, carrier bearing preload/oil film... Will it get you closer than you are now? Probably. Will it be right? Probably not.

Yea lots of varibles. But if its cumalative, all that would be takin into account. If I dont allready have damage, it will probubly be OK. (at least until I can swap it)

[cajunrebel]

YMMV= Your Mileage May Vary. I am watching this pretty close. I have a loose pinion myself and changed the crush sleeve but couldnt get it to crush. My springs just kept flexing. I will try putting something to stop the pinion from rotating up and try again when I get back. I found out this week that my bronco that I have not gotten running needs to drive cross country in March.

[helirich]

Originally Posted by cajunrebel

YMMV= Your Mileage May Vary. I am watching this pretty close. I have a loose pinion myself and changed the crush sleeve but couldnt get it to crush. My springs just kept flexing. I will try putting something to stop the pinion from rotating up and try again when I get back. I found out this week that my bronco that I have not gotten running needs to drive cross country in March.

If you have the yoke, you can just use a big pipe wrench to hold it. I see in the video Alvin posted, they used pretty long bars. (I had a long breaker bar, but I didnt extend it with a pipe.) I cant get back on mine for another week. (at work)

Thanks for the translation

[cajunrebel]

I have a large piece of flat steel that is drilled to fit the yoke and is bolted up and supported by the jack stand. It is not rotating the normal direction a pinion rotates, it is wrapping the leaf springs and rotating the entire housing. It is rotating on the same axis as the tires, not the driveshaft.

[Steve83]

Originally Posted by helirich

Yea lots of varibles. But if its cumalative...

Originally Posted by Steve83

But with hypoid gears, it's not...

Those variables aren't directly-proportional to the preload or to the rotating torque.

Originally Posted by cajunrebel

I will try putting something to stop the pinion from rotating up...

Originally Posted by cajunrebel

It is not rotating the normal direction a pinion rotates...

Why are you working in that direction? You're wasting your effort. Use the pinion bolts to attach a bar that keeps the pinion from rotating the SAME direction that you're torquing the nut.

[helirich]

Originally Posted by Steve83

Why are you working in that direction? You're wasting your effort. Use the pinion bolts to attach a bar that keeps the pinion from rotating the SAME direction that you're torquing the nut.

I think he is doing that except he's got the bar horizontal on a jack stand. I would recomend letting the bar on the floor. (Like in my pic) then it will have less leverage to rotate.

[helirich]

Originally Posted by Steve83

Those variables aren't directly-proportional to the preload or to the rotating torque.]

What I meant by "takin in to account" was on that particular axle. I realize that two different 8.8s may have different torques to turn the axles. (Like the carrier preload effect) So the mfg. couldn't give a figure. But on one particular axle on a given day (oil temp) should take the same torque to rotate the axle now and in ten minutes from now.

The only thing I'm unsure of is if it takes 10 in/lbs to rotate the axle and 15 to rotate the preload, can I assume it will take 25 to rotate the two assembled.