As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEPARTED PDX RAISED GEAR FOLLOWED BY LOUD BANG, VIOLENT SHAKING. INDICATIONS WERE RED UNLOCK LT AND NOSE WHEEL GREEN LT. SERVICED NOSE STRUT WITH FLUID AND AIR. ADJUSTED NOSE LT AND RT LANDING GEAR SQUAT SWITCHES. GEAR SWING AND OPERATIONAL CHECKS SATISFACTORY. WORK WAS ACCOMPLISHED IAW MM 32-20-00 AND 32-60-00.