I swapped my B4 and sc10 gearboxes round a while ago and altho I found the B4 ok with the geared diff the SC10 came off worse. The problem I had was that to get the ball diff loose like the gear diff it slipped like crazy but when I tightened it so it didn't slip the back end became snappy and unpredictable. I was running on a grass track so it may work better on a different surface but I prefered the gear diff generally. Horses for courses I suppose
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