Yes sorry to say to a fellow racer, but have you built it correctly?
I have run the DEX410 for 10 months now and only had to replace one spur gear due to one tooth breaking off, the car still ran, just noisily!
Make sure you have the slipper set as the book and then my advice would be to back it off one full turn, that way you are not unduly stressing the transmission or creating heat in the slipper.
