What was found
AIRCRAFT EXPERIENCED NOSE WHEEL SHIMMY. A NEW SHIMMY DAMPENER INSTALLED. THE USUAL PRECAUTIONS AND TROUBLESHOOTING PROCEDURES WERE UTILIZED TO DETERMINE SHIMMY DAMPENER. WITHIN A FEW HOURS, ACFT REPORTED WITH SAME PROBLEM. INSTALLED NEW SHIMMY DAMPENER MFG BY COMMERCIAL ACFT PRODUCTS (CAP P/N C100016-1A) AND THIS FLIGHT REPORTED NO SHIMMY. S/N 638 MFG 7-97. ANOTHER UNIT, S/N 574 MFG 1/95 FAILED IN LESS THAN 2 YEARS AS WITH S/N 596 MFG 4-96.