What is the purpose of the rubber part on the bottom of your truck

Can you be alittle more specific about the location,size,shape and things of that nature

 

I assume the driver is talking about certain aerodynamic add-ons to reduce drag and make the truck more slippery
https://www.freightlinertrucks.com/Trucks/Models/Evolution/Aerodynamics/

 

It's to help Freightliners increase fuel economy by .000000000000000001% annually.

 

Its just a trim

 

They have ones that auto-deploy at 35 mph. Not sure if they auto-retract or not though

 

The rubber part at the bottom of your truck is the tires. You can safely remove them, it makes your ride a little stiffer but improves your fuel mileage.

 

it serves a couple of purposes, and if you look at many of cars and pick up trucks, and vans built since at the very least, the 1980's, it is to allow for airflow around the vehicle. to reduce the coefficient drag of the vehicle.

now the other purpose is to actually redirect air up and into the radiator for better cooling. if you ever took notice of say some cars built in the 1980's, they had a very small grill for cooling.



this is a pic, of an 1989 ford taurus. notice nearly no grill..??

then look below, see the "air dam"....??

if this breaks off, get it replaced, as this forced cooling air up and into the engine compartment.

many people simply tore it off. and threw it away.

then the car suffers from low air flow to keep it cool.


on big trucks, the front (air dam) lets it go around for better wind resistance, and also allows the air to be forced up into the engine compartment.