Re-Running The Sitemap Generator - Do I need To?

I have been cleaning my forum and I have deleted many posts and threads.

When I do this, do I need to delete my sitemap XMLs and re-run my sitemap generator?

What is the best way to handle this?

Maybe i should redirect the threads and posts in the future instead and move them in to a junk folder perhaps?

I know Google will have a fit because of indexed URLs but I have no choice if I want a clean board.

Suggestions anyone?

Thanks in advance!

The pages will 404 and eventually drop out of the index. It shouldn't pose a problem.

But yes, when you do major changes that remove urls, its always best to delete xml.gz files from data/ and re-run the sitemap generator when complete.

Thanks a lot for the info Brian!