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25 or 28 spline??

Scrusy

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Can anyone tell me how many splines i would have in my diff if my wagon is stock as rock before i got to it. Executive, originally auto (now manual) and rear drum brakes. Looking for an lsd thats all.
 

K-BAGZ

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BTR 0575 / BW 75 Series = 25 spline axle shaft.

BTR 0578 / BW 78 Series = 28 spline axle shaft.
 

Munz

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VN LSD diff would be an easier option
 

Cava454

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Vn LSD is longer as well tho.
 

Scrusy

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BTR 0575 / BW 75 Series = 25 spline axle shaft.

BTR 0578 / BW 78 Series = 28 spline axle shaft.
Is that a code i could read off the diff tag?
 

frogsta

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I thought most commy's were 28 spline I think they started using 28 from VL onward ?
And you can read it somewhere, not sure if it's on the tag though but K-Bagz will know
 

Munz

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only VL Turbo and V8 use the 28spline
 

VR38

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Do the centres intercange?
 

Scrusy

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Is everyine 100% its gunna be 25 spline. Just dont wanna go out spend a few hundred on an lsd and it be the wrong spline
Cheers fellas
 

K-BAGZ

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Identification locations:
- Axle housing - number faces chassis.
- Differential cover plate flange tag - Can reference this number with Holden.
- Different centre carrier housing.
- Bevel gear.
- Pinion gear.

You will most likely have the BW 75 Series open centre differential with a 7.5in crownwheel and 3.08:1 ratio gear set.

My ute was a stuff around when I did some modifications. I have:
- BW 75 Series axle housing
- BW 78 Series 28 spline axle shafts
- BW 78 Series LSD differential centre.
- BW 75 Series 3.45:1 gear ratio with shot peened gears.

Differential centres are interchangable but you match the axle shafts to the centres, or change the axle spider gears. Also you can't fit BW 78 gear sets in BW 75 Series axle housings as the bevel gear is too large, being 7.8in instead of the usual 7.5in. They will fit though, only if you machine the rear pinion bearing cup surface down by approx 3mm. You can however, install BW 75 Series gear sets into a BW 78 axle housing as long as you add approx 3mm of shims to the rear pinion bearing cup surface.

BTR Engineering and Borg Warner manufactured the live axle setup for various makes and models.

I hope this answers your questions, feel free to ask more.
 
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