My '99 Runner has LSD differential. I've researched over the net how this differentials work. But my confusion is regarding what type of LSD the runner uses (vcs, torse, etc..). My other question is, does the LSD is permanent, meaning that is working al the time, or only when 4wd is enabled or low range?

The other question is, in this kind of truck with this lsd, what happens when you engage Lo Range, does powers splits 50/50 and uses 4wd or just transmits power to the rear wheels. I have a lot of confusion about this. I know that in Low range the truck multiplies it power, but what I don't know is if it uses 4wd while engaged and how this affects the LSD.

The last question is regarding Rear Locker, is this the same as LSD or is it different?

Could you guys help me out?

Thanks

JJ

JuanSJO what makes you think your 4Runner has a limited slip differential? Is this what you are meaning by LSD?

The rear electric locker-a switch to the left of the steering column- locks the output of the rear differential so that both sides engage with equal torque.

As configured from the factory it will only allow you to operate the rear locker in the 4wd low setting. That can be changed-but I am not recommending it to you.

Yes, when you are in "low range" you are in 4 wheel drive and the front half shafts are then engaged to allow the front wheels to pull the vehicle as well as the rear wheels to push the vehicle.

I hope this helps....you are sort of new to 4 wheel drive?

Hi, thanks for your response. Yes, I'm very new to offroading, I've done some, but very basic, that's why I've done several postings here.

When I refer to LSD is for Limited Slip Differential. For what I have read on Wikipedia and Howstuffworks LSD works by distributing forece equally to both wheels in case one slips. But in your post you mention that there is a button that locks the rear differential, I infer from this that the LSD is activated by this. In my case I don't have this button, but the differential has the legend "Use only LSD Oil", there goes my confusion and also in case that with no button the LSD is permanent I want to know if it works always or just when enabling 4wd with LO range.

Thanks,

JJ

An LSD and a Locking Differential (locker) are two different things. Lets forget about about the locker for now since you do not have one.
As you have already discovered, the LSD is a mechanism that does exactly what the name implies. It send power to both wheels under equal traction conditions (normal roads) but when one wheel tries to spin faster than the other it sends power to the slower wheel. LSD's work great offroad and will improve your traction noticably by preventing wheel slip before it happens, but if you do lift one wheel completely into the air the LSD will reach its limits and that wheel will spin. This situation is where a locker is needed.
The LSD will always be working, it does not matter if you are in 2wd, 4Hi or 4Lo, it is completely unrelated. There is no way you can ever turn LSD on or off.
Also, when you are in low range you are in 4wd.
JuanSJO, you are very fortunate to have an LSD. US vehicles do not have them for some stupid reason. Do you have the 3.0lt diesel engine too?