What was found
CLIMBING THROUGH 33,000 FEET WE HEARD A LOUD NOISE & THE ACFT BEGAN TO VIBRATE. SUSPECTED GEAR DOOR OPEN. RETURNED FOR LANDING, GEAR EXTENSION WAS FASTER THAN NORMAL. NLG DOORS STAYED OPEN WHEN GEAR WAS RETRACTED. R & R NLG DOOR SEQUENCE PROX SWITCH IAW AMM 32-63-03, DID NOT FIX. R & R LG SOLENOID VLV IAW AMM 32-33-04. OPERATIONS CHECKED GOOD. SOLENOID PN 2225-0100-003 & SN 470. CHECK VLV ASSEMBLY 4 PN 22410001001 & SN 2022.