As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK. FLIGHT CREW REPORTED NR 1 ENGINE VIBRATION ON CLIMBOUT AT 20,000 FT. NR 1 ENGINE WAS SHUT DOWN AND AN EMERGENCY WAS DECLARED. AIRCRAFT RETURNED TO PHX WITHOUT INCIDENT. THE NR 1 ENGINE IS IN THE PROCESS OF BEING REPLACED. AN ADDENDUM WILL BE ISSUED WHEN CAUSE OF FAILURE IS KNOWN.