Narrative:

Installing 1 B-300 and 1 B-700 nose tire pair on aircraft X. Arrived at ZZZ complaining of a nosewheel shimmy. I removed 2 nose tires from our storage rack to take them out to the aircraft for change out. I did not check the tags nor did I look for the green 'washer' indicators to verify that I had either 2 B-300 or 2 B-700 nose tires. My installation followed procedures laid out in the amm for nosewheel removal and replacement. My logbook entry was made and the plane dispatched without a maintenance delay. As I was filling out the a and B sections of the serviceable tag I discovered the discrepancy in part numbers of the tires that I installed. Maintenance control was notified immediately at discovery of the incident of mismatched nose tires (1 B-300 on l-hand and 1 B-700 on r-hand side).

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Original NASA ASRS Text

Title: A B737-300 ACFT MECHANIC REPLACED BOTH NOSE TIRES DUE TO NOSE SHIMMY ISSUE. TIRES WERE MIS-MATCHED. LH TIRE FOR -300; RH TIRE WAS FOR-700 ACFT.

Narrative: INSTALLING 1 B-300 AND 1 B-700 NOSE TIRE PAIR ON ACFT X. ARRIVED AT ZZZ COMPLAINING OF A NOSEWHEEL SHIMMY. I REMOVED 2 NOSE TIRES FROM OUR STORAGE RACK TO TAKE THEM OUT TO THE ACFT FOR CHANGE OUT. I DID NOT CHK THE TAGS NOR DID I LOOK FOR THE GREEN 'WASHER' INDICATORS TO VERIFY THAT I HAD EITHER 2 B-300 OR 2 B-700 NOSE TIRES. MY INSTALLATION FOLLOWED PROCS LAID OUT IN THE AMM FOR NOSEWHEEL REMOVAL AND REPLACEMENT. MY LOGBOOK ENTRY WAS MADE AND THE PLANE DISPATCHED WITHOUT A MAINT DELAY. AS I WAS FILLING OUT THE A AND B SECTIONS OF THE SERVICEABLE TAG I DISCOVERED THE DISCREPANCY IN PART NUMBERS OF THE TIRES THAT I INSTALLED. MAINT CTL WAS NOTIFIED IMMEDIATELY AT DISCOVERY OF THE INCIDENT OF MISMATCHED NOSE TIRES (1 B-300 ON L-HAND AND 1 B-700 ON R-HAND SIDE).

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.