Gmail contacts phone number format?

Everyone has a tendancy to want immediate answers, but in forums like this you need to have a little patience. Anyway, it's possible that your phone is syncing all of your contacts instead of just My Contacts from your Gmail account. To change this, go to...

Contacts -> Menu -> Display Options​

Then select your Gmail account, and you'll see a list of groups with check boxes next to them. At the bottom of the list (you may need to scroll) you'll see All Other Contacts. Make sure that group is not checked.

If it's already unchecked, my next suspicion is that somehow contacts are being added to your My Contacts group automatically. Gmail used to do this at one time, and quite a while ago (several years I think) gave us the option of turning this "feature" off. Unfortunately I couldn't find anywhere in Gmail (PC web-based interface) to turn this on or off. So if this is what's happening to you, I'm not sure what the next step would be.

And, I enter numbers with dashes and it works fine. I don't know if it will display them with any particular delimiters if you don't put any in yourself though.