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tips, technology, tools and techniques related to vehicle driveline components

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tr8todd
Todd Kishbach

(390 posts)

Registered:
12/04/2009 07:42AM

Main British Car:


re-splining axle shafts
Posted by: tr8todd
Date: August 11, 2017 06:55AM

I'm in the process of narrowing one side of an Explorer 8.8 rear end. Called Mitchell driveline about having the longer axle shortened and resplined to match the shorter. I was told that in order to do this, you had to remove at least 4 inches of shaft. Guy on the phone didn't seem very knowledgeable. He put me on hold a couple of times to go ask someone else what I thought were fairly easy questions. Can't understand why you would need to remove so much. Anybody have any ideas or can dispute this claim. I ended up just ordering 2 new axles. Since they were uprated direct replacements, they were cheap enough. $225 delivered for the pair sure beats going to the junk yard and removing two and then haggling over the price. Ever since the Jeep guys started installing these Explorer axles, you'd think they were made of gold. Use to be I just had to get them before the Mustang guys found them. They were anywhere from $75 to $150 for a complete disc brake limited slip unit with a piece of driveshaft. Now they want $400 for the complete units. I'd buy them 2 at a time to get both short axles. Now I'm left with a stash of long axles, housings, rusty brakes, and 3.73 limited slip carriers.


ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1165 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

authors avatar
Re: re-splining axle shafts
Posted by: ex-tyke
Date: August 11, 2017 10:38AM

Here's what Moser Engineering has to say:
A. The axle shaft has to be the same size or bigger as the original spline OD where you need it cut.(They can NOT be smaller )

B. On the original axles you need to be taking off at least 3 1/2″ to get past the original spline area.


minorv8
Jukka Harkola

(268 posts)

Registered:
04/08/2009 06:50AM

Main British Car:
Morris Minor Rover V8

Re: re-splining axle shafts
Posted by: minorv8
Date: August 13, 2017 01:58AM

I narrowed a TR7 rear end 20 years ago, a total of 5 inches. Axles are of different length so LH axle was just perfect when fitted to RH sidd (or vice versa...) Anyway, this left only one axle to be shortened. Diameter was not a problem. But, the axle was induction hardened deep and too hard to have new splines cut. So I was left with 5 in shorter axle without splines. It took some time but I finally found a guy who had proper tools (boron nitride) and I got my splines. IIRC the axle was heat treated along its complete length.


tr8todd
Todd Kishbach

(390 posts)

Registered:
12/04/2009 07:42AM

Main British Car:


Re: re-splining axle shafts
Posted by: tr8todd
Date: August 13, 2017 06:31AM

Talked to my machinist buddy and he says that trying to get the cutter to line up perfectly with the existing splines is extremely difficult and just not worth the effort to even try. Cut them off completely and start again or buy new ones seems to be the only options.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: re-splining axle shafts
Posted by: BlownMGB-V8
Date: August 13, 2017 10:30AM

Cutting splines is a slow process. You can do it with a mill, a dividing head, and a single point carbide tool in a fly-cutter if you have the machine time available, but buying the axles ready made is a better option.

Jim


Orange Alpine
Bill Blue

(45 posts)

Registered:
12/20/2010 07:36AM

Main British Car:
1967 Sunbeam Alpine 2.5 Ford Duratec

Re: re-splining axle shafts
Posted by: Orange Alpine
Date: August 16, 2017 09:30AM

The factory splines are rolled into the axle. This requires the axle to be turned undersized, as the rolling process displaces steel and increases axle diameter. If you examine your old axles, you can see the splines are higher than the turned diameter of the axle. The custom axle guys do not roll spines. They cut them, so they need final spline diameter axle. That means cutting off the turned portion of the axle.

Bill


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: re-splining axle shafts
Posted by: BlownMGB-V8
Date: August 16, 2017 10:55AM

Also. there is a sight strength advantage to rolled splines due to work hardening of the metal, and surface quality is usually a bit better. Provided adequate spline engagement this is usually not an issue.

Jim



roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: re-splining axle shafts
Posted by: roverman
Date: August 22, 2017 11:48AM

FWIW., I have also heard, some production axle shafts were "female broached". Might want to be leery of swapping axles, side to side, in high powered applications. Axles can take a twist, set and don't like to be un-wound. Good Luck. art.


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