440 eng.& 727trans.from a Winnabago

The 440 is rebuilt & trans but I think My cars trans is geared differtly than the passenger car because it's from a Winnabago (truck) it tacking (RPM) 2100 and my speed is only 50 mph rear end gear ratio is taged 3.23. My question is Are 727's trans. gear differently for trucks and cars and if so don't they both have a final gear drive ratio of 1.1. It's a 73 eng. trans combination... No overdrive.