i'll post my results when i find what it is thats causing this. The lower hose isnt collapsing. I dont think airflow is an issue as the temp doesn't drop even at 40 or 50 mph. Everything is brand new except the water pump. its not really that hard to remove. I may pull it tomorrow. Also when i was testing this it was 45 degrees outside. So the temp should have dropped some @ 40 mph.