Why does this work? (s15 helical related)

[e1_griego]

My diff is NOT repeat NOT an s15 helical. It is from a Nissan, but apparently from a cedric/gloria. Those came with 29spline output shafts, but all s15 diffs require 30 spline!

Alex

I recently purchased an s15 helical (with output shafts) from a seller on ebay--got it for cheap too!

Went to a local shop to have it installed. After getting the internals all bolted in, it was time to put in the output shafts. One of the s15 ones had a bent lip, and was a tiny bit chewed up on the lip (looks like they were removed with a pry bar instead of a hammer--completely fixable though). In any event, we just stuff my open diff output shafts in, and they dropped right in and work fine!! This completely contradicts nearly everything I've read about the s15 helical.

(the dirtier output shaft is the stock open diff one)
http://img.photobucket.com/albums/v168/e1griego/IMG_2825Medium.jpg

http://img.photobucket.com/albums/v168/e1griego/IMG_2830Medium.jpg


So, what gives? The diff that was in it had recently changed fluid (at least it came out pretty clear looking). Both sets of output shafts fit the same way, with no forcing or anything at all. It's all bolted in and I've put nearly 1k miles on it since installed--no noises, no grinding, tons of grip. And what a sweet diff might I add!! Perfect for the driving I want to do (ie. not drift), silent, and gives great traction!

Just very curious as to why this works? The guys at the shop chalked it up to "don't believe anything/everything you read on the internet." I'm inclined to agree but it's all very interesting.

Thanks.

Alex

[drew935]

If it works then you don't have to worry about it anymore right. So need to try to figure it out as to why it works. Nissan already did that R&D and is just not telling us. Now take a drive and have some fun. :2f2f:

[e1_griego]

Hahaha fair enough.

Curiosity killed the cat, right ? ;)

Alex

[ManoNegra]

First time I hear of it too. Also curious to find out.

[supad0rk]

Yeah if your diff explodes in a few days for unknown reasons it would be nice to know, probably would be good for you to know ahead of time if its about to too. Just make sure that it in fact is working correctly and isnt doing anything it isn't supposed to.

[Rittmeister]

I actually tried my open-diff outputs in my S15 diff, and they did NOT fit. They were the same diameter as the S15 outputs, as far as I could tell but the spline count must have been different.

[e1_griego]

Yeah, that's what I thought.

That's why I was so confused.

I'll check the spline count on the output shafts when I get home.

Alex

[Chrischeezer]

does your car have HICAS?....
thoes axels look like hicas axles

[GSXRJJordan]

Hicas cars had VLSDs, those are open diff 6 bolt output shafts (not axles). Also suprised that it worked.

[e1_griego]

Yeah, just counted the splines on the hlsd output shafts--- 29 spline, not 30. They drop right into the open diff center section.

Weirdness.

Alex

[swwifty]

are you positive thats a S15 LSD?

[FusionR240sx]

hmmmmm. so far i like... i might try.

[nlzmo400r]

20bucks says you got a vlsd

[orion::S14]

Doesn't look like a VLSD to me...

I'd bet it's a OBX helical...aren't those designed to work in a stock open diff housing?

That'd solve a coupld mysteries:

1) Why it was cheap

2) Why open diff output shafts work

- Brian

[swwifty]

20bucks says you got a vlsd

+1

when you had the diff out, could you see any little tiny gears through the holes in the side of the diff? That's the easiest way to identify a helical diff.

No noise or nothing? My S15 LSD has a nice high pitch whine above like 30-40+mph. Then again you may not hear that since I have all my interior stripped out.

[e1_griego]

YES! You could see the goddamned helical gears. Jesus, I'm not that much of a moron.

Plus, you can feel the car kick power to the outside wheel when it starts to spin the inside wheel.

It doesn't look at all like the obx diff either.

Obx:
http://xs67.xs.to/pics/06064/obxhsld.jpg

My s15:
http://img.photobucket.com/albums/v168/e1griego/IMG_2830Medium.jpg

Someone else's s15:
http://i9.photobucket.com/albums/a53/nismosilvia270r/hlsd1.jpg

It is most definitely a helical, and an s15 one at that. I picked it up from ebay-- here's the auction:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=007&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=170075195837&rd=1,1

Alex

edit-- You're right, I do hear the faintest of whines, but only at 50 or 60+.

Oh, and here's another pic where you can actually see the gears:
http://img.photobucket.com/albums/v168/e1griego/IMG_2827Medium.jpg

[jrbump]

I was there when it was put in, saw the teeth myself.

Both the old and the new shafts popped right in.

This was done at unnatural inc in Beaverton by an experienced technician.

I was amazed myself as this contradicted all my "e-knowledge"


We need someone else to give it a try as well.

[swwifty]

interesting. I have no answer. I know that I had to use my outputs shaft with my s15 LSD though. Maybe you got some freak output shafts. I wonder if there are any other output shafts that will work with the S15 LSD other than the factory ones.

you got that LSD for really cheap, nice job!

he's selling another one on ebay for about $400 which is still hella cheap.

[e1_griego]

Yup, it was a steal, no doubt. Well worth twice the money, too.

Alex

[R33GTS-T]

i'm still curious as to how your open diff s13 6 bolts fit right in when nobody else has been able to get their s15 to work w/o running the s15 helical output shafts :wtf:

if this isn't some kind of a factory fluke and everybody has just been wasted $250 or so on he s15 output shafts then i'm gettin my ass a new diff sooner than expected :rawk:

- Daniel

[sean350z]

No noise or nothing? My S15 LSD has a nice high pitch whine above like 30-40+mph. Then again you may not hear that since I have all my interior stripped out.

Yea so does my VLSD...and my interior isn't all stripped.

Were the bolts that hold the diff onto the ring different fitting than your open diff? I know that S15 diffs use a 13mm bolt and stock is something like 12mm.

[e1_griego]

I honestly wasn't concerned with the bolts, so I didn't really closely inspect it. It all seemed fine though.

Alex

[e1_griego]

Sorry to bump this, but I figured I'd update.

My diff is NOT repeat NOT an s15 helical. It is from a Nissan, but apparently from a cedric/gloria. Those came with 29spline output shafts, but all s15 diffs require 30 spline!

Alex

[pbcstylez]

thank you for the clarification!

[DJ_Sunrise]

is it a helical though? :)

-Bart

[nlzmo400r]

^^ wondering the same thing! Do the glorias come with an hlsd that would work with stock 29spline shafts?

[e1_griego]

Apparently so. It is most definitely a helical-- as I pointed out earlier, you can see the ends of the gears sticking out, just like the s15. It's not a vlsd (for the 10th time !! ;) ). 100% sure it's a helical.

I've had two different people tell me now about the existence of this diff (after the fact and all the confusion). Hopefully someone here can confirm since I'm striking out on google with better facts/details. As soon as I found out better info, I'll post it up.

But it is definitely a helical.

Alex

edit: are the pictures not showing up?