To be totally honest with you if you want a monster truck then buy something else...these Cen vehicles handle small wheels and tyres a LOT BETTER than they handle big ones due to thier puny axles etc, the diffs seem to hold up ok but the dogbones bend and break, as with the cvds. I have broken a fair share of wheel axles as well. I think they have improved the diff cups somewhat, but whats the point really if the other stuff is still bad...
Maybe if you dont bash it too hard and go easy on the BIG AIR you will be ok tho...
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