I am replacing my damaged radiator in my 07 JK. What happens if I do NOT reinstall the plastic shrouds and flaps (attached with plastic pop fasteners). Will it cause a lot of extra noise? Airflow issues?
Thanks

 

I suspect it could reduce the amount of air going through the radiator and subsequently degrade it's ability to cool. When the vehicle is cruising at highway speed those flaps probably help create a bubble of higher pressure air in front of the radiator. With lower pressure on the back side it would create some acceleration of air through the radiator. Either that or they keep the bug guts out of the engine compartment

 

I agree it does control air flow. I doubt it will make any noise without those pieces

 

Air will take the path of least resistance and that's why vehicles have shrouds around the radiator.