Ok, I have searched and talked to several vendors on this one. I have a non sport 5AT sedan, with an "open" dif. I want a LSD, either factory or aftermarket.
My undersatnding is that teh 3.3 gears require a special case, that is not interchangeable with the other cases. The only aftermarket units I hav found that list an auto application are Quaife, and Cusco. The Quaife is no longer available in teh US, however they will be happy to import one for 2 grand. No one I have spoken to is sure weather the Cusco is trully interchangeable or not, and may or may not be available. So it looks like if I want a LSD it going to be a factory unit, or a used QUaife. I understand I have to swap out the out put shafts, along with the differential. Is there a part/ or serial number, I can use to identify a LSd versus an open diff, if I buy a used factory unit?

 

No, there's no such thing as a special case. I just swapped my open diff to a complete 6mt VLSD diff from a coupe.. everything bolted right in without any problems. The 5at and 6mt open/lsd diffs are both the same.. To install an aftermarket LSD in an open diff pumpkin, you just have to swap the gears out of the factory VLSD.

 

When I refferred to case I ment the Differential itself, not the hogshead/ third member.

 

Just find yourself a 3.5vlsd out of a g or z and swap it in.A lot of the fi guys want the 3.3 instead of the 3.5 rear so they can be found.I did the same thing about 4 years ago and its a direct swap.

 

Quiafe no longer avail in US????... I got mine from UltraRev several months ago... it looks like they still sell it... I found a 5% off coupon when I ordered - Google search and you might find one...

here's their site with the ATB Diff on sale:
http://www.ultrarev.com/manufacturer...ufacturerid=59

 

I'll check it out. They actually still list on teh Quaife website, but when I enquired they told me they were no longer available.

 

Order through UltraRev... it was cheaper when I got mine...

 

I just got off the phone with Quaife America… as you stated they are no longer carrying the Quaife ATB Diff because it is not cost effective to import it any longer (they can’t offer it at the price they did previously)…

However, they are developing their own version of Alternate Torque Biasing Differential that is very similar to Quaife but (according to them) has potentially better internals. Their version will be roughly the same price as the Quaife previously was and they anticipate it being production ready in or around June.

Very interesting to me… If I didn’t already have one I’d consider getting their version.

Here is their alternate website that gives a little info… OP, you might want to follow progress of this, it could be a good option:

http://www.autotechdriveline.com/a_index.shtml

 

I believe I might follow up on this. I am not in a hurry, unless I run across a used uniot or something, sounds like this might be a good option.

 

I guarantee that the AT 3.3 diff and the the MT 3.5 diff are different. I have a 2.8 diff that uses the same unit as the 3.3, I originally bought a VLSD out of a 3.5 to get it installed. No one knew what the 2.8 used and after many calls, the few companies that knew did sell 2 different parts. So I had a 3.3 VLSD Pumpkin, the 2.8 Pumpkin and the VLSD out of the 3.5. I brought the 2.8 Pumpkin with the 3.5 VLSD to a shop who determined that it would not fit. As the conversations with the manufacturer's, there is a difference of 10mm offset. I then brought them the 3.3, which they swapped the guts for me.

 

That's too bad about the Quaife!
I had one on my G & they're great, it made a huge difference

 

That is exactly what i was told, there is a 10 mm difference between the 3. diff and the 3.5 diff.

 

I have a 5MT and I also wanted VLSD. I bought a Quaife made for a 6MT and all I had to do to make it fit was swap in the 3.5 gears from a 6 MT. Those are the only parts that needed to be replace to make everything fit. The problem is the main drive gear. The 3.3 gear is 10mm thicker, so if you swap in a diff for an MT, the gear will no longer fit. You need the MT gear as well (because it is thinner).

 

they used to make a spacer... unless you are FI you might as well go shorter gears (3.7-4.0) which will work with the MT Quaife... for FI that want 3.3 they need spacer because I don’t think Quaife makes the AT version anymore...

Or wait for Autotech (Quaife America) version of ATB… they might offer AT 3.3 and MT versions…

 

WOW I looked up a Quaiffe for a 2006 G35 and they want $1400.00 for one!

WTH!

http://www.ultrarev.com/manufacturer...ufacturerid=59

I think I will skip that.