I see on area 52 some time ago this news
Team C is currently testing an optional gear differential to used over the stock ball differential when needed. Gear differentials are a common sight these days in 2WD buggies and SC trucks as they are easy to fine tune, long lasting and also make for very good acceleration on grippy tracks. The diff sits in a prototype gear box (that's the white part) but will very likely come with the usual black colour part once it becomes available for public. Team C has not released any official information on availability yet but according to Axel Toivonen of Euro RC the option part may be available later this Spring and of course fits the Team C 2WD Short Course trucks also.
And know i would like to now when this news will arrived.