first off...

your ram size is fine, i would make sure all your fittings and hoses are the size i have on this picture..

i did hours of endless research on the best way to get reliable steering.. wether its TG or PSC or Surplus Center parts, you need start with this diagram.

you could have a number of issues..
1. you either have an issue with your tapping on your box - isolate your steering  by pulling your lines and cap them at the fittings at your box.
2. you can hook up your lines backwards  ( IF the ram hoses are connected backwards, the steering box and ram will fight each other and you will not be able to control the
position of the wheels. If you feel major binding in the steering, check to see that the hoses are connected correctly.)  - easy as swapping

3. and if that doesn't work you have a bad seal in your ram, i had a bad seal in my 8in ram.. they are super easy to goober up..




Blaaaahhhhhhhh