As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: FLIGHT CREW REPORTED THAT THE LEFT BRAKE FELT LIKE IT WOULD GRAB SUDDENLY WITH A JOLT, ENOUGHTO FEEL A SIGNIFICANT THUMP. MAINTENANCE REPLACED THE MAIN LANDING GEAR #1 TACHOMETER AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK.