How do I test an LSD?

[t-tony]

You get a message (Or used to?) saying "standrad vehicles of this type can be safely tested using RBT"

Tony.

 

[t-tony]

If you ask at the Test station and they can’t/won’t give you a definite answer you can insist on a Decelerometer brake test.

Tony.

 

[DiffManDave]

Are we sure about this? would really like a definite answer not that I don't trust your experience Tony its just the M diff is not Torsen @DiffManDave can you advise?

If you roller test a plated diff it will pit extra wear in the plates, that’s if you can keep it in the rollers.
No problem roller testing torsen

 

[GZed]

Do all 2.8 Z3s have an LSD - and if so, are they all Torsen?

 

[t-tony]

If you roller test a plated diff it will pit extra wear in the plates, that’s if you can keep it in the rollers.
No problem roller testing torsen

At what speed would the wheels have to turn to cause damage to a plated Diff. Dave?

Tony.

 

[Lee]

Do all 2.8 Z3s have an LSD - and if so, are they all Torsen?

Most do, you will need to check your Vin to be 100% sure. It will be a torsen. Only M's come with a clutch pack diff.

 

[DiffManDave]

Do all 2.8 Z3s have an LSD - and if so, are they all Torsen?

At what speed would the wheels have to turn to cause damage to a plated Diff. Dave?

Tony.

its not the speed of the rollers, it’s the length of time it’s sitting in them with only one wheel going round. The rollers would give a false reading anyway as the frictional torque of the plates would be picked up as brakes binding.

 

[Sean d]

So the advice that we have been in the past has been wrong to say that we need lsd oil in our torsen diffs

 

[motco]

That’s the sound of the friction plates rubbing against each other. Nothing wrong with it, just a noise.
I liken it to dragging a chair across a floor, sometimes it makes a noise, sometimes it glides smoothly.
It’s fixed easily with an oil supplement called Friction Modifier which allows the plates to slip smoothly rather than “slip, stick,slip,stick”

Perry's cured the noise within a service visit so I suppose they did as you suggest. An astonishing level of competence for a main dealer, though! My previous two company cars were Leyland Princesses looked after by Henlys and their techies all passed the Henlys Central Scholl of Incompetence exams with flying colours. Details on request...

 

[DiffManDave]

So the advice that we have been in the past has been wrong to say that we need lsd oil in our torsen diffs

Indeed, there’s no friction material in there so no need for special oil

 

[t-tony]

its not the speed of the rollers, it’s the length of time it’s sitting in them with only one wheel going round. The rollers would give a false reading anyway as the frictional torque of the plates would be picked up as brakes binding.

I find it difficult to accept that the wheels turning independently for approx. 15 - 20 seconds (x4) would damage a diff. I may be wrong. Also the Diff. "drag" would be the same for both wheels and wouldn't show as an excessive reading.

Tony.

 

[the Nefyn cat]

So the advice that we have been in the past has been wrong to say that we need lsd oil in our torsen diffs

Hence the question. I'd often wondered if proper LSD oil was needed, but the advice always seemed to be to use it. Now we know better. It can't have done any harm, but if/when I get round to changing it some 75/90 will be going in.

 

[DrWong]

Coming from a BMW background, I only use Castrol.
Syntrax 75-90 for torsen, 75-140 for plated. You can’t go wrong

Great that we have the benefit of your knowledge DMD

I bought some 75-140 (so apparently misadvised!) that I haven’t used yet. Should I not put this in my Torsen and get some 75-90 instead?

Thanks mate