I have been told that they do. I know for a fact that I do not have one, and will be needing one for the upcoming season. I just want to know once and for all if they do or don't.

 

How do you know that yours is not a Limited Slip Differential?? Could just be that your clutch disks are all worn out and need replacing. Did you open it up and check the setup??

Just saying this since it would be a considerable design difference in the event that it didn't have a LSD (sounds too much like drugs). I wasn't even aware that the rear end was offered without LSD functionality.

 

Every single one of them came with LSD.

 

All FDs came with Torsen LSD, as such there are no clutch disks to wear out, and special "friction modifiers" need not be used in the differential oil.

 

jumprdude is right. ALL FDs have LSD and there aren't any clutch discs to wear out.

Lerch32, you can't know for a fact that you don't have an LSD. If you have a FD it has a torsen limited slip.

Jeff

 

you guys are right about the fds having torsen lsd but i think it would be nice to point out that the reason lerch doesn't think his car has one is because they don't work like a typical lsd. a torsen, torque sensing differential, works like an open diff until a wheel starts to spin. then it works like a limited slip, feeding torque to the wheel that isn't spinning...kinda like the best of both worlds, but if your looking for a conventional locked diff you won't find one in any fd3s.

 

Actually there are, maby my lingo is a little off. In the LSD you have friction plates on each side, thats how you get the LSD action. When they start to wear out, you get problems like this.

One of the biggest problems that you will have is improper alignment of the ring gear with respect to the pinion. If this happens, you will get uneven wear of the friction plates in the LSD and the car will eventually start to favor one side under hard load. You will see this if you have an inexperienced installation of a new pinion or ring gear, even a replacement of the internal bearings or oil seals. If they didn't check the placement of the adjustment shims or they put the wrong bearings on the wrong side this will happen eventually because the ring and pinion are not aligned perfectly (and they must be perfect!!).

Consider yourself lucky if this is the problem. Worst cases of this I have seen the pinion gear head break off in the rear diff and sometimes explode out the side of the case like a loose projectile.

Reinstall should be done by a qualified tech so they replace all the proper bolts, bearings, oil seals and shim it correctly. You might have to get your ring and pinion replaced if they wern't aligned correctly (basically they are worn to each other at a bad angle).

In all, might be cheaper to find a junk yard rear end and do a swap if your LSD is beyond rebuild and your ring and pinon are also worn incorrectly.

Here is an example of an aftermarket LSD -

LSD RX7Trix

Good luck with it!!

 

Torsen LSDs do not have a friction plate! The friction necessary for operation comes from the natural friction in the movement of the worm gears within the LSD. These gears do not wear out in the course of normal operation.

Here is a link to describe the operation of the Torsen LSD:
Torsen LSDs

The KAAZ LSD you posted is not a Torsen LSD.

 

Learn something new every day. So I will eat my words with this quote from the page that was listed by jumperdude-

Thanks jumperdude and turbojeff for setting me straight on this one. Talk about some weird stuff. Car just never ceases to amaze me at all the engineering that went into its constuction.

 

The torsen lock-up is based on torque and internal rubbing friction, as noted. For me, too much lock occured for wet weather driving, with just redline 75w90 gear oil, which includes the friction modifier for lsds. I added an extra mini-bottle of redline modifier (slippery stuff), for a little less lock ... worked for me.

I change annually when doing 5+ road track events. goes in typical tan, comes out black ... lots of friction heat.

 

Thank for all the great info guys!!!