Why are my URL's changing

[JillB2013]

My rankings suddenly dropped and when trying to understand why I realized that nearly all images in Google's cached version of my site were missing. In the actual site they appear but in the cached version they don't.

I noticed that most of the images had a ?6b5830 at the end of the URL and these were the images that were not showing.

I am hoping that I found the reason for the drop in rankings. Maybe since Google cannot see a lot of the content it decided not to rank it as well (particularly since it seems to happen on thousands of pages).

This is a cached version of my site

I am using the following plugins that might be causing it: Yoasts SEO plugin, W3 total cache.

1. Does anyone know what is causing ?6b5830 to be added to the end of most of my URL's?
2. Could this be the reason for the ranking drop?

Thanks in advance!

[ThompsonPaul]

W3 Total Cache is what's adding these URL parameters, Jill. It's done so that you can expire the long-term cached version of those images quickly and automatically should the image need to be updated. (This can be controlled in W3TC's settings)

And no, in my opinion there's no way this could be the cause of a rankings drop.

There have been some major fluctuations in search rankings around 7,8,9 May. Is that about the time frame you saw the sudden drop? Many are speculating that Google applied another Panda algorithm update very recently.

Paul