I was able to write my query against the VarChar(4000) data type. This worked.

Update [WBPROD].[dbo].[TASK_SCHEDULE]

Set TSKSCD_DESCRIPTION = Replace(TSKSCD_DESCRIPTION, '<timezoneId>0</timezoneId><timezone>America/New_York</timezone>', '<timezoneId>1</timezoneId><timezone>America/Chicago</timezone>')

Update [WBPROD].[dbo].[TASK_SCHEDULE]

Set TSKSCD_DESCRIPTION = Replace(TSKSCD_DESCRIPTION,

...

Thanks. I did not even know there was an XML Data Type. The data I am working with is stored in a VarChar(4000) column. Good to know.

Here is what I ended up doing which works perfectly for my needs.

,Right('0'+ Convert(VarChar, DateDiff(ss,Coalesce(WBITRAN_START_DATE, WBITRAN_CREATE_DATE),Coalesce(WBITRAN_END_DATE, GetDate())) / 3600), 2) + ':' +

Right('0'+ Convert(VarChar, DateDiff(ss,Coalesce(WBITRAN_START_DATE, WBITRAN_CREATE_DATE),Coalesce(WBITRAN_END_DATE, GetDate()))...

Thanks for the replies. Good stuff.