Ah, perhaps the famous RED WHEEL disease has struck.  Pull the speedo and 
check for a cracked, press-fit gear on the outside of the odo shaft.

Common problem when resetting the odo and it binds, you push a little harder
on the reset and you start the split in the press on wheel.  

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         ___  / __   __/   ____/         Al Knoll HP Performance Technology /
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