What is the larger ground transport vehicle in Prometheus? Is it in the RPG?
Weyland Exoplanet Vehicle Division Rover Transport 01 (RT01).
It is well detailed in ALIEN: THE BLUEPRINTS p122-126 along with the EUV01 quad ATV on p127.
I don't think its been detailed in the RPG materials so far, but the base machine was the Tatra 8x8 military vehicle so that might be a start statting it out.
We live, as we dream -- alone. ~ Joseph Conrad