Any one interested in the oiling mods I did?

There are some similarities in your example but the big difference is one of pressure. The air in your Ram is not a 60PSI system, it's almost no PSI. As you noted, as soon as your imposed a little backpressure, the airflow evened out. The amount of backpressure you imposed was very small, too.

Imagine if you changed to a 35HP air blower so that it would put out 60PSI even with the driver's side wide open. The passenger side would blow all kinds of air. That's because there would be 60PSI in the system and the air would be seeking a place to escape. It's not going to 'work' to maintain 60PSI out the driver side when it can just blow out the passenger side.