What was found
RIGHT MLG LANDING GEAR EXTENSION DID NOT EXTEND - UPON GEAR DOWN SELECTION 6 MILE FINAL 28R SFO RIGHT MAIN GEAR DID NOT LOCK (NO GREEN). ADVISED TOWER TO EXECUTE MISSED APPROACH UPON GOING AROUND THE RIGHT MAIN GEAR LIGHT TURNED GREEN. RAN THE QRC CHECKLIST LEFT GEAR DOWN AND LANDED WITHOUT ANY FURTHER PROBLEM. RANG OUT RH DOWNLOCK SWITCH RESISTANCE WAS HIGH COMPARED TO THE LH DOWNLOCK SWITCH. LIGHTLY TAPPED RH DOWNLOCK SWITCH AND RESISTANCE DROPPED TO WHAT THE LH DOWNLOCK SWITCH READS AND WHAT THE NEW ONE IS READING. REMOVED RH DOWNLOCK SWITCH AND INSTALLED NEW RH DOWNLOCK SWITCH MM 32-30-40. ADJUSTED THE DOWNLOCK SWITCH IAW MM 32-60-00