Many manufacturers do not cover motors under warranty, as it could have been under or overgeared (improper / mis-use, resulting in failure).
Im not saying Traxxas will NOT cover your motor, but it is possible because of the above reasons.
Call them up, it's the only way you will know for sure.
Fusion Hobbies / www.horshamrc.org
The wife stops me being sane and the r/c stops me from going insane....