purpose of the stock fender liner / bumper drop down in front

What is the purpose of this part of the liner that hanges down? I have a slight rub at full turn in reverse on a slope so I'm going to trim it off, which I assume will be fine ... but I am stumped on its purpose? I thought it was part of the bumper but after looking I think it's the fender liner.
Thanks!

 

to tell you the tires you installed are too large....sorry, couldn't help it. I don't know their real purpose

 

Air flap. Break incoming air so it doesn't hit tire harder, while helping in fuel economy.

Those break the air path and redirect airflow to other ways. Just like a boat's nose, opening path for slitting water flow.

Aero tricks available on many cars, maybe for the last 20 to 30 years

 

To hold leaves and debris.
Always picking crap out of hole on the bottom.

Seriously though, I have no clue.

 

Cut it off ,I cut mine off .

 

I took mine off when it rubbed there. No issues

i did keep them just in case!

 

Both of mine ripped off when I backed out of the tire shop after getting 285s. On 2012+ they are held on with push clips, they look to maybe be integrated into the splash shield on the pre-facelift taco.

 

Gone

 

... at least the last 15 years ... i'll be sure to track the fuel economy before and after lol ...

2005 is definitely integrated into the liner. Thanks everyone. They're coming off this weekend if I can get around to it.

 

Took mine off. This simple mod added 10hp.

 

I trimmed mine off to fit 285s. No major issues but I will say a lot more water gets into the engine bay now... I noticed it a lot driving in the snow this past winter and it’s obvious when I drive in heavy rain.

 

On the water intrusion issue just remember the air intake is in the inner fender passenger side so yes they look kind of stupid and then the tire issue but if you remove you may suck water up into that inner fender air intake - not sure so anybody seen that issue? Anyone made a simple flat replacement to clip in its place?

 

Dang it! Can't get the laughing emoji to work!

 

Wow, now that thar is some high-tech knowledge right there!

 

hahahaha!

 

Mine came off when I trimmed for 285's. Never made a difference.