I installed protractor following this tutorial and when i use webdriver-manager update it says:
selenium standalone is up to date.
chromedriver is up to date.
Just add the "preprotractor":" npm install chromedriver" to your package.json
That will down load the latest one all the time.
On windows, I was having trouble with a project that ran fine on my mac. The command that finally got it done for me was:
node node_modules\protractor\bin\webdriver-manager update