OBX LSD: 568 vs 523

[TurboGLH]

So why wont the OBX work with the 3.85 set up? What is the problem that calls for the main shaft and ring gear ?

The 520/523/543 use a conventional ring gear, and just so happen to have almost the exact same dimensions as the neon T350 diff, which is why the obx works in those transmissions.

The 555/568 on the other hand are a bit weird. In order to use 4 pinions, the carrier had to be solid all the way around. But that removes the normal opening into which you would install the spider/pinion gears in a regular diff. So what Chrysler did was to make not only the ring gear, but the entire bottom of the diff unbolt, exposing the inside of the carrier and allowing for the spiders and pinions to be installed.

Since the obx only fit's in a 520/523/543 because they share the same diff design there is no way to use it with the very unconventional 555/568 "ring gear". In addition, since the tooth count and pitch on the 555/568 mainshaft matches on the 555/568 "ring gear" you have to install the mainshaft that matches the ring gear you wish to use, in this case the one from a 520/523/543.

Now, if you want the lower gearing, you can use the 3.77's from a 92+ 523/543. They retain the conventional ring gear and are as close to the original 3.85's as is possible while still allowing for the use of an obx.

[Millerman340]

Thanks for the insight Chris, I don't think I've read exactly why..Dave.

[2.216VTurbo]

Thanks for the insight Chris, I don't think I've read exactly why..Dave.

Yeah all that transmission knowledge in his head AND a damn fine racing event announcer too Although I really really wanted the quick 8 spot ...

[TurboGLH]

Yeah all that transmission knowledge in his head AND a damn fine racing event announcer too Although I really really wanted the quick 8 spot ...

I'm honored, but fairly certain that you have the wrong person. I didn't go to SDAC, and I've never been to Cali so I believe we have a case of mistaken identity.

[2.216VTurbo]

I'm honored, but fairly certain that you have the wrong person. I didn't go to SDAC, and I've never been to Cali so I believe we have a case of mistaken identity.

Oh, Sebrings son, not Ramsdale's son. Got it, I did some drinking with the gang last night

[Mario]

I' putting 300+ HP and 350+ftlbs thru my OBX 523/hybrid and it's happy so far. I can't tell the difference between the Quaife and the OBX by driving them, they both work seamlessly to lay power to both wheels Fantastic mod for any FWD making more than 250 HP or so...

Out of curiosity, do you still stand by this statement. I'm having trouble deciding between the two.

[2.216VTurbo]

Out of curiosity, do you still stand by this statement. I'm having trouble deciding between the two.

Have not dynoed the TC yet but I switched from the Clutchnet DF clutch to thier stage IV six puck ceramic disc with the hi PO PP. Broke it in all careful like for 5-600 miles. now when I get the boost above 17 PSI in 5th, even that clutch wont hold the torque So I cant say what the exact numbers are but they should be in the neighborhood
I had refered to.

Still the OBX has given me no trouble at all and it functions exactly the same (from the drivers seat) as the Quaife in my GLHS

Ill be putting an OBX in my Rampage over the winter

[Mario]

Sounds like I'll save a few bucks then. Thanks.

[minigts]

Can I ask a question about the 568/523 hybrid? The OBX that is for the 523 (I guess), can it be used in the 568 or do you need an LSD designed for the 568?

[cordes]

Can I ask a question about the 568/523 hybrid? The OBX that is for the 523 (I guess), can it be used in the 568 or do you need an LSD designed for the 568?

You would need to use the Quaife that is specifically for the 568. I don't think OBX works for the 568, but since the hybrid uses the 523 diff it would work for that.

[minigts]

You would need to use the Quaife that is specifically for the 568. I don't think OBX works for the 568, but since the hybrid uses the 523 diff it would work for that.

Ok, that is what I was wondering. So you can use parts from the 523 IN a 568 and then get the 523 differential? Just confirming. Because if this is the case and the 523 LSD is a lot less than a 568, why not go that route?!?

[cordes]

Right. If you have a 568 trans and you want to use an OBX diff you need a main shaft and ring gear out of a 523. You then need to have the gears from the 568 put on the 523 main shaft, and all the work that goes along with that done to get the 568 back together.

In the end I don't know that you would save any money. However if you are making decent power the potential for a 3.50 FD from the 523 donor would be very nice.

[2.216VTurbo]

Ok, that is what I was wondering. So you can use parts from the 523 IN a 568 and then get the 523 differential? Just confirming. Because if this is the case and the 523 LSD is a lot less than a 568, why not go that route?!?

And that's what I'll be saying unless I break a 523