j30 axles in S13

[maxtherabbit]

Let me start by saying that I have read the 800 articles on swapping a j30 diff and axles into the s13. Yes, I know everyone in the wide world of internet says they work fine.

That said, I am concerned about track width. I know the j30 has a wider track than the s13 (at least by 1" maybe 2", can't remember) so doesn't that mean that the j30 axles will be a bit longer?

I've currently got a z32 n/a diff with 6-bolt outputs from a j30 and my stock s13 axles, the only reason I'm considering the j30 axles is because they are beefier. But it seems it would defeat the purpose to swap in axles that are being crammed in to a shorter track, thus wearing out the tripod joints prematurely.

[djsilver]

J30 rear track = 58.9"
S13 rear track = 57.5"
S14 rear track = 57.9"

So the J30 track is 1" wider than the S14 and 1.5" wider than the S13 but 800 people have done it? I guess the only way to check for yourself would be to install them without the rear coilovers in place, then swing the suspension through it's full movement to make sure they don't bind. Because of the LCA arc, it would most like be at full droop or full compression.

Are J30 axles tripod on both ends like the 240sx? I thought they were tripod on one end and CV joint on the other?

[maxtherabbit]

hmm good question, I've got a couple 5-bolt j30 axles sitting around guess I'll pull the boots and check em out

[maxtherabbit]

edit - according to this guy the early 5-bolt j30's are BDO

looks like they're going in, I'll do the bind test

[Epstein]

I've run J30 axles in an S13. They fit. It was a very long time ago. I can't remember if this was related to the problem where the inner metal grease seals eject themselves or not.

Also, I wouldn't take any measure of influence from "this guy". It was him that convinced an entire throng of people to "revive" their VLSD by adding more shims. Those shims are to set the spider gear engagement, and do absolutely nothing to affect the VLSD section of the diff. Any increase in "locking" was the result of their spider gears binding, which was also not long-lived.

[maxtherabbit]

good call, I saw his bit about the shim and saw through that quickly. they are BDO joints though, I just opened them up to confirm that. but I think I'm going to hold off on installing them for now because their minimum length is in fact longer than the 240's. whether this will necessarily cause problems I don't know without testing, but I could definitely see the seals being pushed out by the joint and hemorrhaging grease into the output flange.

when I snap my first axle maybe I'll give em a shot...

are there any other readily available options for stronger half shafts or is it just a "get em made" type of situation? or do you guys just stockpile 240 half shafts?

[Def]

I've run J30 axles in an S13. They fit. It was a very long time ago. I can't remember if this was related to the problem where the inner metal grease seals eject themselves or not.

Also, I wouldn't take any measure of influence from "this guy". It was him that convinced an entire throng of people to "revive" their VLSD by adding more shims. Those shims are to set the spider gear engagement, and do absolutely nothing to affect the VLSD section of the diff. Any increase in "locking" was the result of their spider gears binding, which was also not long-lived.

I remember that stupid zilvia trend. I think some people still do it.

It's a good way to tear the crap out of the spider gears in your rear diff and lose some HP at the wheels...

[Matt93SE]

adding a phantom grip to your VLSD? sweet. If you're a loser.

[logr]

Are you guys sure it's the axles that are longer? Try putting a J30 vlsd in a 240 diff and you will see what I mean. One side shaft won't go in all the way. I have a J30 in the race car with a helical and stock 240 axles. Didn't really check for axle bind though.

[Epstein]

I think you're referring to another J30 difference based on year. The thick side shim goes on the side opposite of every other R200 I've used. I'm pretty sure this trait is inherited from the thickness of the 3.9 ring gear. This shifts the carrier over, which changes what the length of the shafts needs to be. The solution is to shorten the end that doesn't go in all the way, and put new cir-clip grooves in the correct location.