What was found
UPON GEAR RETRACTION , THERE WAS A LOUD "THUD" WHICH WAS FELT AS WELL AS HEARD. WHEN THE NOISE OCCURED THE ACFT MOMENTARILY YAWED. TROUBLESHOT PROCEDURES IAW MM 32-30-00. PERFORMED LANDING GEAR CONTROLS MANIFOLD INTERNAL BLEED RATE, OPS CHECKED GOOD, SERVICED NLG OLEO IAW MM 12-10-38. PERFORMED GEAR SWINGS, OPS CHECKED GOOD. NO "THUD" SOUND PRESENT. PERFORMED INSPECTION ON MAIN GEAR DOORS & MLG WHEEL ANTI-SPIN, OPS CHECKED GOOD IAW MM, CH 32-42-00. DOWN JACKED ACFT, CHECKED EXTENSION ON STRUT.