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Are those axles out of the same diff that you posted the pic of the hammered ring gear?

I'd be interested to know what sort of engine and gearbox combo caused all the carnage. 

Axle chat is also interesting, over the years I've heard varying opinions on what is the best way to shorten axles, I had one done that had welded axles- Terrano ends with bw center, never gave any trouble, it only had 3.8l of moo power though  

 

 

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26 minutes ago, flyingbrick said:

well you said that it came in out of a bro's car.

I figured you were either A, saying it came out of a mates car or B, being racist, lol.

No, you are right, Brick. He's a very close bro. He looked after my whare' and whanau when I used to contract offshore. But he knows the rules about shed space. He has his own shed. I'm a half caste too. I deride all colors and castes equally, lol!  

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12 minutes ago, cletus said:

Are those axles out of the same diff that you posted the pic of the hammered ring gear?

I'd be interested to know what sort of engine and gearbox combo caused all the carnage. 

Axle chat is also interesting, over the years I've heard varying opinions on what is the best way to shorten axles, I had one done that had welded axles- Terrano ends with bw center, never gave any trouble, it only had 3.8l of moo power though  

 

 

No Clint, that head was (still is here, lol) a 9"  That axle above is from an 8 and 3/4 Chrysler. This will bring warmth to your soul as it did mine, Clint ... Chryslers did the damage in both cases. Both early Hemi's, both with 671's but don't quote me on that because I know there was an 871 in the mix with one of them - but unsure if it made it onto the engine. Glides and mechanical fueling ... you know the story mate - direct drive black belt shit. I love axle talk too. I like hearing about other peoples experiences and passing on my own. Its a specialist area for sure and one where all sorts of shit can happen. Over the years of doing this sorta stuff, I have formed some conclusions about things based on what I have done, seen and read.

These are my people.

684790163_20190316_163435(Large).thumb.jpg.b15f374f8342054e4a872f5f09f86a30.jpg

Churr

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I too was curious as to what kind of torque monster did that to an 8 3/4 axle.  I've seen lengthy debates on the www as to what rear to run in a 9 second car.  Hundreds of replies insisting either 8 3/4, Dana 60, or 9 inch.  

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6 hours ago, RUNAMUCK said:

So you're saying the OEM axles ate made from more betterer material? 

Just some thoughts.

No one knows what material OEM axles are made of except the OEM and you can bet your arse - that they keep that info close to their chest. They are in the car making business to make money. One of the ways they make money is getting ahold of the cheapest material they can get, then turning it into a usable item. This is a very competitive area with massive savings to be had. So held even closer to their bosom is the recipe and cook who mixed this cheap shit all together and got it to a usable state through a proprietary hardening process. You cannot count on this OEM manufactured steel meeting any international standard ie. SAE.

Know that a SAE Steel is made to exacting standards that is thoroughly understood the world over. So much of this added to so much of that etc. Furthermore its thoroughly understood what heat treatment processes are needed to be done to a certain type of steel in order to improve its properties so that it will perform satisfactorily in a given application. This kind of stuff is well know the world over so that standards and consistency are maintained. The Heat Treatment places all know what process an SAE steel needs to meet a certain standard.

This all falls by the wayside when something comes in to a Heat Treatment place that looks like its made of this' but can't be verified as actually being so. And its right at this point here that a lot of bullshit starts involving the OEM axles and the Barry at the Heat treatment place. 

More later.

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I'm willing to bet that OEM axle material is just some specific off the shelf alloy steel (each OEM probably uses a different one though). Hardened exactly as the supplier specified. Car manufacturers don't have their own steel mills and using crap material would be counter-productive as you would need more material (cost) and would likely have less consistent properties (warranty issues).

 

It's really not hard to do a compositional analysis on a piece of steel to find out what the alloy is.

 

Through hardening isn't always the best option either, you generally want some ductility in the shaft.

 

Then again, you might be talking of axles made in the 50's or 60's, I'm thinking more in the last 40 years or so

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5 hours ago, johnny.race said:

Just some thoughts.

No one knows what material OEM axles are made of except the OEM and you can bet your arse - that they keep that info close to their chest. They are in the car making business to make money. One of the ways they make money is getting ahold of the cheapest material they can get, then turning it into a usable item. This is a very competitive area with massive savings to be had. So held even closer to their bosom is the recipe and cook who mixed this cheap shit all together and got it to a usable state through a proprietary hardening process. You cannot count on this OEM manufactured steel meeting any international standard ie. SAE.

Know that a SAE Steel is made to exacting standards that is thoroughly understood the world over. So much of this added to so much of that etc. Furthermore its thoroughly understood what heat treatment processes are needed to be done to a certain type of steel in order to improve its properties so that it will perform satisfactorily in a given application. This kind of stuff is well know the world over so that standards and consistency are maintained. The Heat Treatment places all know what process an SAE steel needs to meet a certain standard.

This all falls by the wayside when something comes in to a Heat Treatment place that looks like its made of this' but can't be verified as actually being so. And its right at this point here that a lot of bullshit starts involving the OEM axles and the Barry at the Heat treatment place. 

More later.

Following on from above ... When commissioning someone to shorten then respline an axle, here are some things to keep in mind. In no particular order If you are having a spline put onto the axle that differs from what was on there OEM, you don't want to be cutting in a spline whose minor diameter (check what it means on the web) is smaller by any significant margin than the OEM spline's minor diameter. Near all OEM axles are case (induction) hardened ie. hardened on the outside and left soft in the middle. Understandably, the more material removed from the 'case', the weaker the axle becomes.

Another thing, what you want to be doing is staying away from anything that involves using extreme heat at the pointy end of an OEM axle.

You want to be staying away from welding - whether that be for cutting and shutting or using a low hydrogen rod to build up the tapered area behind the factory spline in order that there is material there to cut a new spline into. Welding introduces changes in the parent material due to extreme localized heat. A lot of people know that welded axles are a bad idea but then have no problem agreeing with a machine shop to building up the axles using weld. Go figure. Ask the axle what is the difference. What did it say? Nothing. Because there is no difference... it all introduces extreme heat to the smallest part of the axle. If the axle is going to fail - chances are its going to fail there. The weld never breaks. The part where the weld is attached to the axle breaks. Sometimes the machine shop will tell you that the axle will need heat treating afterwards. I'd go somewhere else or seek a different option (different axle)

More stuff. Always ask the machine shop what they are going to use to respline your axle. Ask to look at it. If its not a cutter that features an indexable tip(s) then assume they will soften your axle using heat prior to having at it with a piece of HSS. Walk out. You don't want any heat at the pointy end. 

Ask them how many passes it takes them to cut the spline. Ask to see the side gear they need to check their work. This is not being cheeky. because if they are not using CNC and most will not for this type of work .... they will be using the apprentice. Resplining work is a balls achingly slow and repetitive process, and is very easy to fuck up. A shit respline job (as in undersized and sloppy) will translate back to you as 'excessive backlash' in your diff head. Think about it. Nek minut, its out with the diffhead chasing a problem that is not there. You paid for extra wear on your axles, lol. I am not exaggerating ... this shit happens. Don't listen to naysayers that say it don't - they have no skin in the game.

This is how you really want to approach getting your axle done .... turn up at the machine shop with your axle and side-gear. Let the guy know you know exactly what you are after and how you are going to measure it. Show him the fit on the OEM spline and tell him you want less or the same. Not more. A single pass done by the apprentice in order to save time will almost guarantee and undersized job. You won't know this when you go to pick it up unless you have a side gear to check the fit with in front of them. It all looks shiny upon uplift but shiny does not mean its right.

This is just my take on things. Your mileage may vary.

More later.

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Notice I make judicious use of the term OEM and go to lengths to ensure the reader is reminded that this/these are the type of axles i am talking about above ie. the ones issued by Ford (or whoever) in the bum or your car as original equipment. My thoughts on the aftermarket axles that I've come into contact outlined later.  

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9 hours ago, johnny.race said:

them how many passes it takes them to cut the spline. Ask to see the side gear they need to check their work. This is not being cheeky. because if they are not using CNC and most will not for this type of work .... they will be using the apprentice. Resplining work is a balls achingly slow and repetitive process, and is very easy to fuck up. A shit respline job (as in undersized and sloppy) will translate back to you as 'excessive backlash' in your diff head. Think about it. Nek minut, its out with the diffhead chasing a problem that is not there. You paid for extra wear on your axles, lol. I am not exaggerating ... this shit happens. Don't listen to naysayers that say it don't - they have no skin in the game.

This is how you really want to approach getting your axle done .... turn up at the machine shop with your axle and side-gear. Let the guy know you know exactly what you are after and how you are going to measure it. Show him the fit on the OEM spline and tell him you want less or the same. Not more. A single pass done by the apprentice in order to save time will almost guarantee and undersized job. You won't know this when you go to pick it up unless you have a side gear to check the fit with in front of them. It all looks shiny upon uplift but shiny does not mean its right.

This is just my take on things. Your mileage may vary.

More later.

This is all very good advice!

But to just add something on the end for ya:

You are nearly always better off sending your components to a shop that specializes in whatever task is required. You don't want to pay for a shop to learn how to complete your task.

While previously based at a machine shop i was asked countless times about re-splining of axles and would refuse- We simply couldn't do it as cheaply (as quickly) as a professional axle shop could. Another reason is that i'd seen that machine shop pump out some horribly poor fitting spines!!!! unfortunately if you go a little heavy on each cut it can be hard to know until the very end when a test fit shows it up- and by that stage its too damn late.

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More axle tech/shit. 3 common axles.

P3201625.thumb.JPG.21386e98d84e779362ef3e21d50d2b68.JPG

The shiny outer ring is the part of the axle that has been hardened. The middle is left unhardened. This is done to achieve a balance of strength and durability while still being ductile.

P3201626.JPG.433010b6f7aae4dc9d6db6eba83b403d.JPG

Two examples of spline work. Only one of them is an axle. The top item is a piece of round stock that was used to practice resplining on. The bottom piece is an actual axle. Both pieces feature 30 splines suitable for Hilux. Look closely at them and you'll note that the top piece looks a little bigger about the diameter - even on the spline portion. Given the previous picture showing the depth of hardening ... you'd want to be attempting to remove the minimum amount of material you can from an axle's diameter. 

P3201630.JPG.4672b0fbe514ad74d9564366c755b249.JPG

Furthermore ... the bottom item has been subjected to a shit quality respline job. The person that cut these splines didn't ensure the cutter was aligned the the job. Pfffft. So not only was it undersized (sloppy) it had been cut outta whack too. Someone got ripped, plus it looks like some chatter was going on too a little bit. 

P3201631.JPG.d65d1acaa1e26ffde05fad13db959a15.JPG

Two 30 Spline axles with Hilux side gears slid on.

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Only one of them was a Hilux axle though. This one started life in a BW78 equipped Ford Falcon. A 28 Spline BW78 axle will just' take a Hilux pattern set of spline on it.

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Notice the was minimal machining done to the BW axle diameter prior to cutting in the splines. It only just made the minimum required major diameter.  

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Ahh, diff stuff. 

Here's one of my original 24mm axles I broke in the racecar... It made a mess. 

1.jpg

2.jpg

The original axles were mild steel and had been known to break for the car's entire life (it's got a custom floating axle rear end). 

 

So I got Howat Engineering to make up a couple of moly axles. These were the same size as the originals. The ends were hardened in an unknown way, but you can see the difference in colour on the splines: 

1.jpg

Business end: 

2.jpg

Big end: 

3.jpg

 

Funnily enough, I also ended up breaking one of these... It had created small fractures where the splines mesh into the side gears and broke into a psychedelic star shape which is quite interesting to look at. I think all my broken axle ends are still on a shelf in Dad's garage in Palmy. 


My next step was to get the side gears in the diff taken out the 28mm (same size/spline as an F series Toyota) and then got them electro hardened in Auckland. The current 28mm axles are the same style/manufacturer as the ones pictured above. They've lasted well so far and have taken the abuse, but I'm sure the splines are starting to stretch and wear slightly from my heavy clutch and aggressive left foot (although it doesn't matter at the mo as the car is sitting in the garage... in pieces.)

 

@johnny.race - do you have the ability to make whole axles from scratch like the ones above? Because I might need your services one day. 

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8 hours ago, Truenotch said:

Ahh, diff stuff. 

Funnily enough, I also ended up breaking one of these...

@johnny.race - do you have the ability to make whole axles from scratch like the ones above? Because I might need your services one day. 

Fuck did you?! Lol. I have had something to do with his stuff (Hilux axles for a specialized application) and thought his stuff was pretty good. I have some pics of the axles I am talking about and was (still are) going to post in here showing was was available locally. I don't offer to do what Mr Howat did/does. I stick to a few popular ones and that is it. I know what I know and I know what I don't :)

This said, I hold a view on your particular application that you might find interesting. It involves some of the pics and things you have posted and some of the ones I have too. More on this later. Thanks for sharing your stuff matey. Its an eye opener for sure.

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