What was found
AFTER TAKE OFF AND RETRACTING NOSE GEAR MULTIPLE BANG NOISES FROM NOSE COMPARTMENT, CONTINUED ONCE OR TWICE AFTER CLIMBING AGAIN TO 18000 FT. R & R THE LT MLG UPLOCK BOX IAW AMM 32-30-00. OPS, FUNCTIONAL, AND LEAK CHECKED GOOD. NO ABNORMAL NOISES NOTED.