Rear Diff (Viscous LSD or not)

[Entaran]

Hey guys,

Have a rear diff lying around here with "9A31" printed on it.

Any way of telling if it's a viscous LSD?



Spinning the input shaft is pointless, because it won't lock up until it's warm if it's viscous. It's -definately- not mechanical. Might just be an open one.

 

[Rockabilly]

Pull one axle out & slide a long extension arm inside it. If it slides through
& doesn't hit a step, it is a viscous lsd.
If it has a step & the wheels spin oposing ways, it is a hollow.
If you hit a step & the wheels spin the same, it is a clutch lsd.

 

[Entaran]

I can see straight through it. There's no axles connected. It's literally just a diff.

So in the centre of a hollow or clutch LSD, there's a step that stops a rod going straight through it?

because I can pretty much see straight through this diff with the hole for the axles being no different from end to end. (IE: there's nothing hanging down into the gap).

I need to have a closer look.

 

[Rockabilly]

You have a viscous lsd if it is one dia right through.

 

[bazeng]

yup
i believe if u can see right through, its an lsd

if u turn one axel/shaft.. the other will eventually turn the same way if u spin it fast enough

first time i did mine (ever) it rotated the other direction, after about 5 - 10 rotations, it spun the same way...

check the sticker, does it say viscous lsd?

 

[Entaran]

That's the problem.

There is no sticker.

 

[titan]

If you can see thru the centre of the diff without any obstacles, you have an LSD diff.

EDIT:
Can you take a photo of the driveshaft spline (thru to the other side) and we will be able to tell you whether it's an LSD or not.