Ciudat ce spui, inseamna ca nu e in 4x4 "permanent"(precum Subaru de exemplu) ci mai degraba FWD si in caz de nevoie intra spatele ,in cazul tau probabil ca intrand tare sistemul a reactionat dar dupa ce masina alunecase deja . Din punctul meu de vedere sistemul folosit pe E30 e cel mai "avansat" si citez de pe wiki "These cars use centre and rear differentials with viscous couplings to vary the torque split between wheels. The centre differential has a default front:rear torque split of 37:63, due to the planetary gear.[5] Up to 80% of the torque can be transferred to the tripping axle, using the increasing shear force of the silicone fluid in the viscous coupling (due to the slotted/grooved plates inside the unit) as wheel slip causes one axle to spin faster than the other. The same principle applies to the rear differential varying the torque split between the rear wheels. The front differential has no locking function."
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