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Discussion Starter · #1 ·
If you haven't read yet I'm doing a chevelle with a diesel in it and I want/must/have my heart set on, using a GM corporate 14 bolt axle.

I AM GOING TO NEED TO SHORTEN THE AXLE.

I was watching "extreme 4X4" one day and saw this thing the guy used to align the axle ends and keep them strait so he could weld them. I think its some kind of jig. It's like a long rod that goes threw the axle and squishes the 2 cut ends to thehousing ends. I DO NOT KNOW THAT MUCH ABOUT IT. Does anyone know where to get one of these jigs and info on shortening axles? And probly a place to get a custom length set of axles to.
 

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I always thought a close second to respline would be to cut to length with a 1/4" less or so and a good bevel. Drill and tap both ends with a fine thread. Use a 10.9 stud that has a fat OD but leaves a good wall thickness. Weld and machine to size. If you do good lathe work that takes care of alignment issues.
 

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I always thought a close second to respline would be to cut to length with a 1/4" less or so and a good bevel. Drill and tap both ends with a fine thread. Use a 10.9 stud that has a fat OD but leaves a good wall thickness. Weld and machine to size. If you do good lathe work that takes care of alignment issues.
It's the welding part that's best avoided. That's where alignment can turn to crap and high strength steels are difficult to weld properly to avoid cracking.
 

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Agreed. One can be done at my shop and the the other has to be farmed out. Tend to get good results on stuff like that, but the worst can happen. Resplining is always best.
 

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Discussion Starter · #6 ·
ok I guess I wrote this out wrong.
What I want to actually cut and weld are the axle tubes.
My bad.
I would never EVER cut and weld an axle.
My uncle has axess to a machine shop so turning and resplining is a no brainer there.
 

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ok I guess I wrote this out wrong.
What I want to actually cut and weld are the axle tubes.
My bad.
I would never EVER cut and weld an axle.
My uncle has axess to a machine shop so turning and resplining is a no brainer there.
That makes a hell of a lot more sense.
 

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I understood what he meant the first time...maybe because I watch the tv show.. :)

If you have access to a machine shop...simple to build the jig. "The jig works by using machined pucks installed in the housing ends and carrier bearing caps. A steel rod is then installed through the pucks. If the steel rod will not go through the pucks, the housing is misaligned. "
 

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SEMI FLOAT OR FULL FLOAT Axle???

The rod you are referring to should be (minimum 1.500" Diameter) alignment Bar and should be perfectly straight. Some shops use Heat treated and ground bars to offer the highest accuracy for aligning the housing perfectly. Many people achieve great results using Mild or plain carbon steel bar stock, Drill Rod, or Cylinder stock.

Alignment Process

1.) Pucks that are machined to the outside Diameter of the Carrier Bearing races with a 1.500" bore are installed into the housing one on each side. They get tightened into place with the Carrier Bearing main caps.

The Alignment bar is then passed through the pucks.

2a.) (FULL FLOAT AXLE) You will then have to install pucks that can thread onto the 14 bolt Spindles and hang past the end of the spindle with a 1.500" Bore in them. (these pucks have a Id Thread that has to be single pointed on a lathe)
2b.) (SEMI FLOAT AXLE) Install pucks that have a 1.500" bore and a OD Dia. that matches the outer axle bearing Seats.
2c.) (HYBRID FF) We also use weld on Companion flanges that allow you to use front dana 44/50/60 spindles. To turn a SF axle into a FF with removable spindles. the bushing can either go in the companion flange or the BK bushing in the spindle.

3.) Everything gets tacked in place.

4.) The bar gets Removed.

5.) Final Weld, Let cool.

6.) Check with Bar, Straighten if Necessary.

FYI Ballistic Fabrication sells Alignment Bars and Pucks But you will have to call them to Order.
FYI Ballistic Fab also sells new 14 bolt spindles 5,6,8 lug hubs and nice flanges. So you can use double splined axles.

If you have access to a machine shop you could build all your own stuff to do it but you will have more time Invested. You might consider sending it out to a reputable shop/machinist that has experience do this type of thing. the average price to narrow a housing is Rear axle $200 Front $3-500.

If you take on the Project good luck, take pictures.

Oh by the way if you are talking a SF axle I would suggest building a FF instead.
 

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There's no reason for your alignment bar to be 4130 or 4340. Both of those are expensive steels with no stiffness advantage over any mild or plain carbon steel.
 

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Discussion Starter · #13 ·
yeah I'm just gonna use inco x750 any ways, lol. ;)
I didn't know I could get 5 lugs for a 14 bolt, ehh I'd rather go with the 8 lugs that way when ppl start staring at the wheels I know I did my job.
And if your keeping up with my other post you'll already know I'm planing on using truck spindles in the front if it'll work.
Any idea of shops that could do this for me?
 

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There's no reason for your alignment bar to be 4130 or 4340. Both of those are expensive steels with no stiffness advantage over any mild or plain carbon steel.
Yes I will agree that you could use mild steel bar stock in this particular application, considering in the 5 years I've been apprenticing for a machinist who has been building axles for 30+ years at his business, That I've seen factory housings with more than 1/16th out of alignment. I’ve also seen many bent housings that work for Rec Wheeling that actually flex under High loads, and even they haven't all failed yet. I would definitely agree that there is some fudge factor involved.

I will say with a better tool though much tighter tolerances can be achieved. The bar we use is a piece of 1.500 Dia. 4340 that was heat treated, center less ground, and polished 30 something years ago. The pucks we use are a .003 slip fit.

Old tools are cool, The old machinist who made that tool and taught me how to use it is way cooler in my book. :)

Edited: previouse post for two inaccuracies, alignment bar material choice, and BK bearing pucks only work on companion flanges for building a full float axle with Dana 60/50 FF spindle's ...
 

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yeah I'm just gonna use inco x750 any ways, lol. ;)
I didn't know I could get 5 lugs for a 14 bolt, ehh I'd rather go with the 8 lugs that way when ppl start staring at the wheels I know I did my job.
And if your keeping up with my other post you'll already know I'm planing on using truck spindles in the front if it'll work.
Any idea of shops that could do this for me?
you can get hubs to make the ff down to 5x5.5" and if you ar erunning a sf you can make what ever pattern you want.

there is even a kid on pirate4x4 that has a 14bff 10.5" diff that has had the outers modded to 5x4.5" semi floating shafts.
 

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ask around and look for a shop near you that way you dont nead to ship it, most good welding shops can do that sort of thing.

hope this helps

TAYLOR
 
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