What was found
(CAN) INTERMITTANT PROBLEM ON THE LANDING GEAR RETRACTION SYSTEM IN THE UP POSITION ONLY. SOMETIMES THE 'GEAR IN TRANSITION' LIGHT STAYED LIT AND, ON ONE OCCASION, THE GEAR DOWN SELECTION COULD NOT BE DONE OTHER THAN BY THE MANUAL SYSTEM. MANY GEAR RETRACTIONS WERE DONE ON THE GROUND. DYNAMIC BRAKE RELAY INSPECTED AND FOUND A BAD CONTACT ON THE UP SELECTION. CONTACT CLEANED, FAULT CLEARED.