What was found
DURING DEPARTURE, JUST BEFORE LEVEL OFF AT FL410, PITCH TRIM MISCOMPARE ON PFD ILLUMINATED. IAW CHECKLIST THE AUTOPILOT WAS DISCONNECTED AND CREW HAD TO USE CONSIDERABLE AMOUNT OF CONTROL COLUMN FORWARD PRESSURE TO MAINTAIN LEVEL FLIGHT. FOUND PITCH TRIM WHEEL FROZEN IN FORWARD POSITION. AN EMERGENCY WAS DECLARED AND THE ACFT DIVERTED. UPON REACHING 8000 FT THE TRIM WHEEL RELEASED AND SYS RETURNED TO NORMAL. LANDING WAS UNEVENTFUL. MX LUBRICATED THE ELEVATOR TRIM ACTUATORS. FOUND WATER CONTAMINATION IN OLD GREASE. DURING OPS CHECK FOUND THE ELECTRIC TRIM ACTUATOR RESPONSE TIME OUT OF MM LIMITS. THE ELECTRIC TRIM ACTUATOR WAS REPLACED. A SUCCESSFUL OPS CHECKED WAS PERFORMED. ACFT WAS RETURNED TO SERVICE.