I have experianced this with my savage and it usually due to braking hard or braking str8 after a jump when all the weight is still on the front wheels.
like everyone else has said, mesh it quite tightly and loosen the slipper off. at least you'll know which car is yours, as it will sound like a bag of bolts

__________________

Website:
http://www.wbmcc.co.uk/bingham-model-raceway.html
Schumacher Cat Xls, Rc10 Team(retired), Mardave Cobra, SST 98 Rally Car, TT02 Rally car, Wpl-c24 and Element Enduro builders kit #71 #deaddogracing
Autocare, unit 5 candleby Court, Cotgrave NG123RT.