TheSamba.com :: View topic

Fri Jun 29, 2012 3:15 pm

Why would my GM dealer offer to put nitrogen in my wifes car tires?
It was included in a comprehensive service and checkup.
Do others use nitrogen in their tires. Maybe I've been in my cave too long. LOL
Marvin

Fri Jun 29, 2012 3:31 pm

In our racing cars we run nitrogen in the tires. This is because compressed air is full of moisture and with heat air will expand which changes the pressure in the tires.

So running nitrogen you get far less pressure differentials as temps go up and down.

But the main reasons shops put nitrogen in passenger car tires are because it is less likely to migrate out through the rubber of the tire.

So your tires should stay up to pressure longer then they did with just air. Less need to check pressures on a regular basis.

And since nitrogen has less moisture content then you get with compressed air, there should also be ess corrosion inside the wheel.

larger quantities of moisture build up can also play funny games with wheel balance, so that sort of trouble is minimized also with the use of nitrogen.

But the real reason is so they can charge you an extra $10.

Fri Jun 29, 2012 3:44 pm

Thanks drscope.
Marvin

Fri Jun 29, 2012 3:57 pm

Worst thing about filling the tires with nitrogen is, how the hell do you know your tire is full of nitrogen? How do they evacuate the air? What percentage is necessary to get the benefits?
They could fill them with unicorn farts and you'd have no way to know the difference.

Fri Jun 29, 2012 4:34 pm

Derek Cobb wrote: Worst thing about filling the tires with nitrogen is, how the hell do you know your tire is full of nitrogen? How do they evacuate the air? What percentage is necessary to get the benefits?
They could fill them with unicorn farts and you'd have no way to know the difference.

With unicorn farts your VW would levitate. :lol:

Fri Jun 29, 2012 5:25 pm

zozo wrote: Derek Cobb wrote: Worst thing about filling the tires with nitrogen is, how the hell do you know your tire is full of nitrogen? How do they evacuate the air? What percentage is necessary to get the benefits?
They could fill them with unicorn farts and you'd have no way to know the difference.

With unicorn farts your VW would levitate. :lol:

Aren't those pointy? And more expensive than the $10 you get charged for them?

Besides, I thought that they only put that stuff in lip balm.... :?

Fri Jun 29, 2012 8:02 pm

My tires already have 78% Nitrogen.

Fri Jun 29, 2012 8:15 pm

Derek Cobb wrote: Worst thing about filling the tires with nitrogen is, how the hell do you know your tire is full of nitrogen? How do they evacuate the air? What percentage is necessary to get the benefits?
They could fill them with unicorn farts and you'd have no way to know the difference.
usually nitrogen filled tires have a green cap.

Fri Jun 29, 2012 8:30 pm

And unicorn fart-filled tires have a brown cap?

Fri Jun 29, 2012 9:06 pm

dawerks wrote: My tires already have 78% Nitrogen.

mine too! why pay extra money for more?

Sun Jul 01, 2012 8:39 am

air_cooled75 wrote: dawerks wrote: My tires already have 78% Nitrogen.

mine too! why pay extra money for more?
Because 100% nitrogen has 0% moisture.

Sun Jul 01, 2012 9:28 am

shiningstar76 wrote: air_cooled75 wrote: dawerks wrote: My tires already have 78% Nitrogen.

mine too! why pay extra money for more?
Because 100% nitrogen has 0% moisture.

But how do you know there is 100% nitrogen in there? Just because they told you so?

Sun Jul 01, 2012 10:24 am

I've found that by filling all four wheels of my daily driver with Helium there is an amount of lift created that reduces the amount of gravitational pull. This is resulted in a 15% increase in gas mileage.

Sun Jul 01, 2012 10:30 am

Wuss, real men roll with hydrogen in their tyres. I figure since the Hindenburg already blew up, statistically I am in the clear.

Sun Jul 01, 2012 11:34 am

the whole point behind this is you probably have the stupid ass TPMS on your car. nitrogen is less likely to cause issues with the air pressure, thus not tripping the light on the dash.

the TPMS is it's own valve stem/map sensor combo. you better hope the tire shop has it's A game, cuz when the break or go bad, it's about a hundred bucks for a new one

it is a crock-o-shit system imho. one more thing to make old ladys pull you off a clutch job to put air in a tire :roll:

Sun Jul 01, 2012 6:03 pm

skills@eurocarsplus wrote: the whole point behind this is you probably have the stupid ass TPMS on your car. nitrogen is less likely to cause issues with the air pressure, thus not tripping the light on the dash.

the TPMS is it's own valve stem/map sensor combo. you better hope the tire shop has it's A game, cuz when the break or go bad, it's about a hundred bucks for a new one

it is a crock-o-shit system imho. one more thing to make old ladys pull you off a clutch job to put air in a tire :roll:

Yep, I agree that it is a crock. Wifes car has the air pressure gauge on each tire with the sensor that is supposed to give the AP per tire. One of the units is bad but I keep all 4 tires checked with a quality gauge.
I was surprised at all the crap it monitors and shows up on the dash as I select the different items. How the heck can it tell when I need to change the oil? I like my VW better. LOL Since it is included in the $65.00 service I'll tell the wife that it's a good deal.
Marvin

Mon Jul 02, 2012 3:10 am

Given that Dr has valid points where tire pressure is super critical (racing) and the reasoning is valid, the variation for a normal car would most likely be minimal.

But, its another revenue generator for shops and I seriously believe that is the primary reasoning.

As far as migration through the tire itself, that would be true if the remaining portion of air (20%ish) was small stuff (like helium or hydrogen), but its primarily oxygen, which is physically bigger than nitrogen. You see nitrogen at mass 28 relative to oxygen at 32 on a mass specrometer from atmospheric air.

Mon Jul 02, 2012 5:40 am

andk5591 wrote:
But, its another revenue generator for shops and I seriously believe that is the primary reasoning.

Well not really. Remember the explorer's flipping over? Because of that, it is now gov't mandated.

So are the back up sensors. Trust me it is one more thing us dealer guys have to deal with. The tpms is a sealed battery powered transponder that sends a radio signal to the car.

Its REAL fun trying to diag the system when the scanner picks up the car next to you on the hiway.

Mon Jul 02, 2012 10:35 am

minger wrote: Wuss, real men roll with hydrogen in their tyres. I figure since the Hindenburg already blew up, statistically I am in the clear.
I LOLd.

Mon Jul 02, 2012 11:42 am

skills@eurocarsplus wrote: The tpms is a sealed battery powered transponder that sends a radio signal to the car.

I prefer the EBTPMS.

Eye Ball Tire Pressure Monitoring System. "Hmm, that tire looks low. Let me check with a tire gauge. Son of a gun, it IS low."