What was found
GEAR DISAGREE AFTER TAKEOFF, RT MAIN SHOWED RED. AFTER RUNNING QRH WITH HYD PUMPS ON, RT MAIN SHOWED NORMAL. FLIGHT 5039. TROUBLESHOT GEAR DISAGREE IAW FIM 32-60-07. INTERROGATED PSEU & NOTED STORED CODE S18 FAR RGUPLK. PERFORMED A GVI OF PS7GA SENSOR IAW AMM 32-61-05, & 32-32-05. FOUND SENSOR TO BE GUNKED UP & OUT OF TOLERANCE AT 0186, CLEARANCE SHOULD BE BTWN 035 & 045 IN, NO OTHER DEFECTS NOTED. CLEANED & ADJUSTED SENSOR TO BE WITHIN TOLERANCE IAW AMM 32-61-05. PERFORMED MULTIPLE GEAR SWINGS & VERIFIED GOOD OPS OF MLG & INDICATIONS IAW AMM 07-11-01, NO FURTHER DEFECTS NOTED PER FIM.