NA/NB side shaft query

Garido · Postby **Garido** » Fri Jul 07, 2017 2:48 pm

Question:
Are the NA8 (non ABS) and NB8A (non ABS) side shafts the exact same. I believe they are compatible but the part catalogues show they are different part numbers (unsure of why). I believe the NB had a different sub-frame (wider track) as such, I'm not sure if the actual shaft itself is longer. Because there have been so many cars which have been modified (upgrade diff, widen track, swap sub-frame etc) it's hard to get a definitive answer.

I want to try and eliminate any chance for misinformation. What I do know is as per below.

Catalogues show

NA8 shaft # MD0225500 (non ABS) / MD0325500 (ABS)
NA8 shaft # MD2125500R0A (remanufactured part #)

NB shaft # MD1225500A / BC4C33471 (ABS sensor, possible tone ring???)
NB shaft # MD2125500R0A (remanufactured part #)

So, anyone with a bone stock NA8 side shaft able to measure or do a comparison against an NB side shaft?

hks_kansei · Postby **hks_kansei** » Fri Jul 07, 2017 6:41 pm

Both fit and can be swapped, but each are slight different design.

Na8 is two piece, with a stub axle at the diff, then a flange connecting it to the test of the shaft (including the 2 cvs)

Nb they removed the flange so it was one piece (still with 2 cvs)

Both can be swapped between cars, just the na8 one allows the diff to be removed without having to also pull he shafts from the knuckles.

Garido · Postby **Garido** » Fri Jul 07, 2017 9:49 pm

hks_kansei wrote:Both fit and can be swapped, but each are slight different design.

Na8 is two piece, with a stub axle at the diff, then a flange connecting it to the test of the shaft (including the 2 cvs)

Nb they removed the flange so it was one piece (still with 2 cvs)

Both can be swapped between cars, just the na8 one allows the diff to be removed without having to also pull he shafts from the knuckles.

Is there a difference in length between the 2 designs. Also thank you for your contributions over the many years. As a long time reader (not a large poster) I appreciate the posts you and Keith (97 MXV) have made.

Garido · Postby **Garido** » Fri Jul 07, 2017 10:37 pm

Due to the designs, I'd be curious to know if there's a weight difference?

StanTheMan · Postby **StanTheMan** » Sat Jul 08, 2017 6:34 am

I can't see it being a huge difference.

http://www.solomiata.com/Drivetrain.html

It doesn't go into weights. But some other Info you might consider useful depending on where you are heading with your project.

Garido · Postby **Garido** » Sun Jul 09, 2017 10:32 am

StanTheMan wrote:I can't see it being a huge difference.

http://www.solomiata.com/Drivetrain.html

It doesn't go into weights. But some other Info you might consider useful depending on where you are heading with your project.

Yeah I did check that out but I was hoping for a bit more information. I might acquire an NA8 one and post up some more detailed numbers for the community.

97 MXV · Postby **97 MXV** » Sun Jul 09, 2017 12:01 pm

hks_kansei wrote:Both fit and can be swapped, but each are slight different design.
Na8 is two piece, with a stub axle at the diff, then a flange connecting it to the test of the shaft (including the 2 cvs)
Nb they removed the flange so it was one piece (still with 2 cvs)....

Following info is likely correct but not necessarily last word...
This discussion is about shafts for mid size 7"diffs not for smaller NA6 6" diffs nor for SE Diffs (larger output spline).

Both bare shafts are nominally 24.5 mm diameter, however the 2 piece shaft is necked down to 22.5 mm for most of its nom 300mm exposed length between cv joints, carving about 200g weight from it.
Not sure about strength, but the two piece shaft would be similar weight courtesy of it being necked down a couple of mm.
I do not know why the one piece shaft is not necked over its exposed section. I am unaware of any strength/stiffness issues with the 2 piece shaft, so the change may be a manufacturing cost saving measure or even maybe related to a stiffening the driveline ??

Agree both NA and NB shafts same length and can be swapped between cars, the two piece allows easier diff swaps but leaves less room around flanged joint for large bore exhausts and 2 piece have no ABS tone ring.
Further to this, the later NA8 shafts 96/97 are likely one piece shafts same as NB with ABS tone ring compatibility.
The ABS tone ring will not fit the 2 piece shaft.
One day I might have to get some ABS tone rings laser cut if I ever bother going 2 piece shafts for the easier diff swapping potential of the 2 piece shaft.
I have a set of 2 piece shafts set aside in my collection for one day when I get motivated to fit them with laser cut ABS tone rings.