Diff Shenanigans

[dark.sky]

Hey guys, so those of you who attended Kadina Show'n'Shine would remember what happened to Krishy's car. If you weren't there or were too drunk to remember, he took off, changed gears, and then the car just free revved in gear. Upon further inspection, you could see the tailshaft was spinning into the diff, but no drive coming out.

The diff, a Tomei 2 way 4.11, had been in the car for roughly 3 weeks, after being swapped into the place of the factory A-LSD unit found on some R33 GTS-t's.

With the car jacked up, the LH rear wheel would free spin by hand, and the RH rear wheel had a bit more resistance on it, and would also turn the tailshaft.

We drained out the oil, and saw nothing too major apart from some metal filings. Once out, the first thing we did was remove the cover, and much to our amazement, everything looked quite good and clean. Both of us were expecting to see major mechanical carnage.

We pulled the half shafts out the diff, to find the teeth from the LH side were shaven clean off, but only on the very end, almost like the shaft didnt go in far enough. When we pulled out the other side, it became evident that the 2 shafts were different. Both had 29 splines, and both were the same overall length, but the length of the 'middle portion' is different. I'm assuming this is not meant to be? It looks like the shaft from the LHS wasn't going far enough into the diff centre, and has simply sheared off. The diff centre appears to be fine and in working order, apart from the metal filings from the shaft.

LHS:

RHS:

Can anyone shed some light on this? It would be much appreciated

PS. If anyone knows how we can clear the metal filings out of the diff, that would be a great help too

[Krishy]

Thanks for chucking this thread up Dion. Really appreciate your help with this mate.

Yeah so as Dion has stated its pretty much looks like the 2 half shafts are off 2 different types and one not being long enough to engage into the center properly, which has caused it to sheer the teeth off. Everything else looks good. The working half shaft fits into either side and both sides seem to operate quiet well with that half shaft. All I now need is another half shaft that looks like the one out of the right hand side.

[The Dan]

You said you pulled out an A-LSD.

Did you change the driveshafts as well? You know the A-LSD is about 25mm wider than a standard R200 diff. Is it possible the attached driveshaft actually pulled the half shaft out of the diff slightly?

[dark.sky]

The full driveshafts and diff housing are from a non ALSD R33...

[The Dan]

So from diff right out to hubs is all non-alsd?

[Krishy]

Daniel the diff if from a non ALSD R33. The only things changed where the diff center to a tomei 2 way and the half shafts that do inside the diff. Everything else is still the same from my ALSD Car.

[The Dan]

Daniel the diff if from a non ALSD R33. The only things changed where the diff center to a tomei 2 way and the half shafts that do inside the diff. Everything else is still the same from my ALSD Car.

Then refer to my original post. The driveshafts (CV's + shaft) will be shorter in the A-LSD car because the A-LSD diff is 25mm wider at least. Not 100% sure whether or not it will be a problem but you should check that the driveshafts aren't pulling back on the half shafts.

I could be wrong as I have never physically disassembled the A-LSD driveshafts and compared them to standard driveshafts. They may just slide further out of the tripod CV on the hub side, not sure.

You should also check the half shaft length vs the centre depth to see if maybe they didn't go all the way in or something. The tin shield should go almost all the way up against the seal. If it doesn't, then it may not be all the way home.

[dark.sky]

When you slot the LH half shaft into the diff when outside the car, pushed all the way in, it just free turns, and doesnt spin the diff. Whereas if you put the RH side half shaft onto the LH side of the diff it works fine.

Meaning, when just the half shafts are in play, the LH still doesnt go into the centre far enough.

[Tommy Kaira RL]

It looks like the left shaft would never of gone all the way in. Where it steps out its further up the spline than the other one. And its longer. And it also has ground the last 5mm off the splines. The splines would of gone all the way to the end.

Have you put the right shaft into the left side to see if it goes in ok.

I would guess you need another shaft like the right one.

Hey Krishy were any of those shafts off my blown NA diff that I gave you? Maybe the installer used some of them

[dark.sky]

I'll wait for Krishy to answer the last part of that, but yes we have put the RH shaft into the LH side off the diff and it spins the diff fine.

[Krishy]

It looks like the left shaft would never of gone all the way in. Where it steps out its further up the spline than the other one. And its longer. And it also has ground the last 5mm off the splines. The splines would of gone all the way to the end.

Have you put the right shaft into the left side to see if it goes in ok.

I would guess you need another shaft like the right one.

Hey Krishy were any of those shafts off my blown NA diff that I gave you? Maybe the installer used some of them

Now as for that I cannot actually remember which one was from your diff and which one was from the new one that I bought. As there were many parts around the place and everything got mixed up.

So now I just need another half shaft that looks like the one that came out of the RHS, as that half shaft goes in both sides and can spin the diff without any problems.

[On Edge]

did u ring that guy krish?

[Krishy]

Oh shit completely forgot. Does he have just half shafts lying around?

[On Edge]

dunno he is selling two whole diffs though for $150 each

[Krishy]

Yeah my diff is fine just need a half shaft lol

[rad100]

he only needs the half shafts not the drive shafts

[dark.sky]

Wrong half Damo, haha.