Is the value of Nitrogen gas still a recommended way to inflate a new tire on a passenger car? Why?

Nitrogen molecules are larger than other molecules that make up "air", so in theory it would be harder for them to leak out of tires and out of the "bead" between the rim and the tire. Nitrogen also runs cooler within the tire so there is less fluctuation in air pressure between cold and hot tires.

I work at a dealership that offers nitrogen fills. It is not cheap - around $30 for 4 tires. They have a special pump that sucks the air pressure down to a minimal level, then fills the tire back up with nitrogen.

There are studies that show that having nitrogen-filled tires keeps them at proper pressure longer, resulting in more even tread wear and better fuel mileage.

But, are the savings (benefits) worth the extra cost? Personally, I wouldn't pay for it. If you check your tire pressures regularly (which you should do anyway) I think you can realize about the same benefits as using nitrogen without spending the money.

Nitrogen fill is not BS or without merit. But, it is kind a gimmicky marketing thing that I'm not sure is cost justified.

Better Maintenance of Tire Air Pressure

Because of the larger molecular size of Nitrogen, it migrates through a tire 3 to 4 times slower than oxygen.

Lower Fuel Consumption

Better tire air pressures improve rolling resistance and reduce the risk of running tires under-inflated.

Extended Tire Life

With tires maintaining better pressure, tire life can be significantly extended.

Oxidation is Eliminated

With Nitrogen, there is no more oxidation of inner liners, belt packages, valve stem hardware or air pressure monitoring devices.

Improved Retreadability

Nitrogen doesn’t cause tire rubber to break down as quickly as regular air and with the elimination of oxidation, Nitrogen filled truck tires have often had 4 or more retread lives.

Stronger casings = more retreads.

No More Rim Rust

Nitrogen is completely dry. Condensation is eliminated.

On the Road Reliability

Decreased tire failures reduce costly down time....

The air you breathe is about 78% nitrogen. Using pure nitrogen to inflate automobile tires doesn't really do much for the car. It's more of an advertising gimmick.

Yes, Better Ride