What was found
GEAR DISAGREE WARNING & ASSOCIATED NOSE GEAR UNSAFE WARNING INTO DTW, GO AROUND, QRH, MSGS CLEARED AFTER CYCLING GEAR UP THEN DOWN. COMPLIED WITH PA 05-018 REV K SCENARIO 1. PERFORMED GEAR EXTENSION & RETRACTION CHECKS IAW AM 32-30-00, ALL CHECKED GOOD. FOR NLG SELECTOR VLV REPLACEMENT & WORK PERFORMED SEE NRWC N24273, OK FOR SVC. REPLACED NLG SELECTOR VLV PN 750006000, SN ON 1745 & SN OFF 1298. ALL OPERATIONS CHECKS & LEAK CHECKED GOOD IAW AMM 32-33-10.