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Guys,

How can I verify if the diff I have, is an open diff or a LSD diff?

I can turn about 3,5 times for 1 full circle of a flang. So it's a 3,45 or 3,64
Both flanges turn the same way (there's nothing mounted on the flanges) where they're free of torque.

Is there any sign or marking that's says what ratio the diff is?
there a number on the housing, and a number on the bolted backplate.
Also a mark of 280 or 290 on top op the housing, and HH1 or something like that.

Anyone?

If the half shafts rotate in the same direction. you have led. to be totally sure you will see a letter z or s i think somewhere on the diff.

When turning the left or right flange on an open diff, the other flange will turn the other way. With a LSD the locking unit will prevent the other flange to turn in the opposite direction, so it will turn the same direction. That's basicly the function of a LSD.

On www.hardemanmotorsport.nl you can find out how a differential works. (in dutch)

Should have a white S painted on the case or an s on the diff tag.

With diff of the car the flanges tend to rotate the same way so it not a good test, if you can take the cover plate of you can tell just by looking inside

Jason

True, but you can feel it right away when you try to turn the flanges in opposite directions. With an open diff it’s no problem, and with a lsd it’s not possible.

Unless the LSD is really worn out, then it’s possible with a little effort but then also you can feel the resistance.