Will it hurt my rankings if I change the permalinks so late?

[vulonl]

I think I did something wrong in the past.

My permalink structure is www.keyword.com/postname-keyword

Now my website with over 1000 pages has this structure. Now I really would like to change it to a normal structure like www.keyword.com/postname

But the problem is my website and its page have good authority and page rank and above 100k pageviews monthly.

It will really have a big impact on my business if something goes wrong.

Is it worth the risk to change it? Because now often pages who have nothing related with the keyword have the keyword in the permalink. I think this is really not good for the ranking of my subpages.

Change or not to change?

[TakeshiYoung]

Do you think that the extra keyword is negatively impacting your SEO or user experience? If so, it may be worth it to change the URL structure. Just be sure to triple check your 301 redirects before you go live, and be ready to revert back to a previous version of your site in case anything goes wrong. Expect to see a slight dip in traffic for a week or two as Google sorts everything out.

[vulonl]

Thanks for your reply.

So I finally decided to do this. Now I get 404 errors, so I changed it back in WP. I really want 301 Redirect, some how every plugin I installed cant Automatically detect this.
Someone knows if this is even possible?