Tyre noise - Limited Slip Differential

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: 1998 1.6 NB (JDM)
  2. I’m based near: Essex
  3. I’m looking for technical help or recommendations on: Limited Slip Differential

Apologies in advance for this cross-post from another topic in the General Discussion area.

My JDM Roadster is a 1.6 “Special Package” with a Torsen Limited Slip Differential. I know how the LSD works, but I have had no previous experience driving with one.

Prior to changing the diff oil, the rear offside tyre would regularly “chirp” when turning right out of one particular junction having a slight incline. I originally put this down to the road surface and a cheap Chinese tyre, but the chirp continued after fitting Yokohamas.

My problem is that since changing the oil, not only am I getting the same chirp at this junction, I’m also getting significant momentary tyre squeal on some roundabouts and bends – even at moderate speed. Is this something experienced by others with LSDs?

I suspect the diff oil was unchanged since manufacture (20 years and 100K miles). Might the fresh oil contribute to a change in cornering characteristics where one side of the diff catches up with the motion of the other side?

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Sounds like it is doing exactly what it is meant to do.
Assume the diff allows a up to a 20% speed variation between wheels before the action of the diff limits further variation.
If you now go round a roundabout which requires a greater that 20% variation of speed from the outside to inside wheel then regardless of make, it is going to chirp the inside tyre.

2 Likes
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I agree with NickD.
May be more spirited driving would help? :innocent:

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Thanks.

As I understand it, this type of LSD is gear-driven and does not use clutch mechanisms, so I couldn’t understand why the propensity to squeal the tyres had apparently increased following the oil change.

The weather and road surfaces had not significantly changed, so I could think only of changes in the characteristics of the oil.

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Yes my Mk1 G-Ltd would give a little churp at junctions even at very low speeds.