Maybe you could use a macro.
I'd start looking at one of these references:
Ron de Bruin's EasyFilter addin:
http://www.rondebruin.nl/easyfilter.htm
Or:
Code from Debra Dalgleish's site:
http://www.contextures.com/excelfiles.html
Create New Sheets from Filtered List -- uses an Advanced Filter to create
separate sheet of orders for each sales rep visible in a filtered list; macro
automates the filter. AdvFilterRepFiltered.xls 35 kb
Update Sheets from Master -- uses an Advanced Filter to send data from
Master sheet to individual worksheets -- replaces old data with current.
AdvFilterCity.xls 55 kb
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But I'd insert a helper column with a formula like:
=int(row()/5000)
and use that as the basis for the split.