funny noise and no resistance.

[b4rs]

ok, i took out my buggy yesterday and it seems to be goin same speed as normal but it does not slow down as quick wen i let off the acceleration. it brakes fine but rolls for longer. also when i have reached top speed and i let off the accell it seems to schreach unhealthily to an eventual stop, it doesnt feel like theres any resistance. but it can still get up hills, there is traction. and it doesnt sound good. any ideas would be helpful