So after alot of time and money spent on my brothers volcano S30 it was finally working again! he had a bad crash last year and since its been problem after problem and after finally eliminating all the problems one by one it worked again! but now it has stopped, and i think the diffs are shot but im not sure, i took apart the whole front assembly and i put the driveshaft in and tried to spin it myself, the cup spins, so does the gear when i look at the inside of the diff but the wheels dont spin much, and when its on the ground the driveshaft just spins the wheels dont move, this happens with the front and rear diffs, are they shot?