D30 TrueTrac 3.73U 27SPL
Gear driven limited-slip traction differential, TrueTrac differentials are unique in that they increase traction but do not affect steering or wear out prematurely; these problems are common with limited-slip differentials that use clutch plates and springs. TrueTrac performs like a conventional differential, until there is a loss of traction. Only then will the power transfer occur - when it is needed. Typical TrueTrac differentials are shown above. As with a conventional differential, the TrueTrac side gears are interconnected by pinion gears, which allow one wheel to slow down or speed up as required. TrueTrac gears have spiral teeth, and the pinions are mounted in pockets in the case. If one wheel begins to lose traction, the pinions separate slightly from the side gear, and wedge in the pockets. As input torque increases, the separating force increases, thus slowing or stopping the spinout. This allows torque to be distributed to the wheel with the best footing. Note: TrueTrac differentials require a certain amount of resistance at the ground in order to start the power transfer. A TrueTrac differential may not transfer power if the spinning wheel is off the ground. If spinning occurs, often a light application of the brakes, while carefully applying power, will slow the spinning wheel enough to allow the TrueTrac differential to transfer torque to the other wheel.