is that
7000 10000 5000? what does it drive like?
Don't diif act like this, as I am getting confused
(quote)
The weight of oil in a diff only affects how that diff splits the power (torque, actually) between its outputs - and it only makes a difference when the outputs are wanting to turn at different speeds, i.e. during a corner or when the grip is different between sides or ends (usually due to weight transfer, but also surface changes).
Just looking at one diff - the rear - if you have ultra-thin oil then when the weight transfers to the outside wheel in a corner, the inside wheel has less grip but still gets half the torque, and lights up. The outside wheel is only getting as much torque as the inside one, and continues to grip.
With very thick oil, you get a bit of initial understeer as the diff resists the two wheels turning at different speeds during turn in. Get on the power, though, and the diff diverts torque to the slower wheel (the outside one, since the inside one will try to light up again). This has two effects: firstly, with more torque going to the outside wheel you may well saturate the tyre and you'll start to lose lateral grip, so the tail will begin to step out. Secondly, the outside tyre is producing more forward thrust - because it's seeing more torque - and this creates a moment which tends to turn the car in even harder.
Similar things happen in the other two diffs, with the general result that thin oil gives a consistent car but one that can't make full use of the available traction; and thick oil makes the car reluctant to turn initially, but snapping to oversteer when you're sufficiently hard on the throttle.
Mike
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