jongaines

My SA told me today that MB (Leith in Raleigh) is now offering to fill your tires with Nitrogen for $40. Allegedly, the molecules are larger than O2 and won't leak out of your tires, regardless of heat/cold issues. I said "never", as in "I will never have to refill them"? He said not if you don't have a puncture. Sounds like snake oil to me, but thought I would pass it on for member discussion.

nantucketsleigh

Sounds like magic paint sealer, rust proofing, or window treatments.

mortenmol

Well i've read the same, but haven't tried it myself.
I didn't really check mine the first 16K miles and they didn't even lack 0,1bar.
But one should do it regularly

MB Fanatic

if its good enough for airplanes and jumbojets, its good enough for cars. Costco uses nitrogen at no charge.

vinceching

um... you can get free nitrogen air put in at costco.

costco has been using that lately for all their customers. and even if you didn't buy your tires from costco... if you ask nicely enough... they will do it for you.

the reason they started using nitrogen is because it stays in the tire for a longer period of time and doesn't slowly leak out like regular air.

regardless of if you have regular air going in your tires, or nitrogen ... one should always check their tire pressure at least once every 30 days.

btw, i remember reading somewhere that nitrogen isn't as good for your tires as it degrades the inner tread/material of the tire. not sure if that is true or not.

patsy1099

Does that mean we'd be able to do whippits off our GL tires? Shhweeet.

scottybdiving

It's also good enough for Nascar. They have been using TPMS for a while and using Nitrogen allows them to adjust the pressure in 1/4 lb increments. BTW, air is about 69% nitrogen. If true, I would think running them at a constant desired pressure would outweigh any degradation that could occur.

I have been thinking of doing it myself. Since the TPMS on my Silverado gives actual tire pressure for each tire, I have witnessed up to an 8 PSI swing from cold start to highway. I feel that if I inflate them to the correct pressure when they are cold they will drive overinflated. If I inflate them when they are warm, I get a low pressure warning every morning.

lkchris

Normal air is 78% nitrogen, so you're not gaining much.

scottybdiving

OOps! You are correct. I did my math wrong. 21% O2, 78% N, and 1% other. I am usually only looking at the O2 because when I dive with Nitrox, the O2 level is raised to 32-36%. This means less N absorbed and allows for longer bottom time.

The real benefit of running straight N, is that pressure stays nearly constant as the temperature changes which means less tire wear.

lwain56

A Kia Store here offers it as a package. I'am friends with the GM at that store and his cost per car to re-fill, purge and final refill 4 tires with a huge Ingersol Rand nitogren generator, (kinda of neat as the tech hooks up all four tires to the machine while it does this) is $9.99. Sold for whatever you can get for it, typically $40.00. Nitrogen is a larger molecule and reputedly less apt to have # fluctuations due to weather and creates an atomosphere in the tire that water can not condensate.

jongaines

wow, great minds think alike. I remember it like yesterday [wavy lines-wavy lines], it was the summer of 1980, Reagan in the White House, Pink Floyd's "The Wall" tour in full swing, the diesel station wagon is packed up, including "THE CANISTER" . . . .good times .

Do you think a line from the tires to the passenger cabin would void the MB warranty?

aroby

Quoted tyre pressures are for when the tyres are cold.

lwain56

Heck man that was nitrous oxide, not nitrogen!

StevethePilot

http://www.straightdope.com/columns/070216.html

http://blogs.consumerreports.org/car...nitrogen-.html

And so on. Bottom line; it's a waste of money. Unless you plan on taking your GL to 40,000 feet (or in to space) and hitting the road at about 200mph from wheels stopped, nitrogen not only doesn't make a significant pressure loss difference but doesn't really make a significant dryness difference, as it's such a high percentage of normal air (unlike carbon dioxide, which, despite what Al Gore says, is barely a trace of our atmosphere).

STP (where the "P" this time stands for "pragmatist")

scottybdiving

Last week when we saw a couple mornings in the 20's, my TPMS warning came on and showed the tire pressure to be 61 - 63 psi in the four tires. The recommended pressure is 65. After about 10 minutes on the highway the warning went off as the tire pressures surpassed 65. After about an hour and 45 miles, they were all at 70 - 71 psi. That seems pretty significant to me.

I may get the Nitrogen fills and compare. Of course this week we have been in the 60's - 70's.

vinceching

that isn't a fair comparsion regarding if it is good enough for nascar.

the tires they use and the material isn't the same as consumer based tires. the tires in nascar are subject to higher speeds, wear and other conditions. and most of the time the tires only last for 100 laps or so.

Jon2007E63P30

I have to agree that I do not think I would ever pay for it.

jongaines

Yes, sadly I realize this, but a boy can dream can't he?

StapleGun

Waste of money...aircraft use it because it's an inert gas

scottybdiving

Of course they are different. They do not use Nitrogen to keep the tires from wearing, they use it to keep the tire pressure from fluctuating. They often add or subtract 1/4 - 1/2 lb pressure to one or more tires to tweak handling problems. With tire pressure being that sensitive and dramatic in the way the car handles, they need something that is not going to increase by several lbs when the tires heat up. It has nothing to do with the tire breaking down or how well they will wear. There is always an endless supply of tires for them.

Now whether it is worth the price or not, who's to say. I'm not especially happy, now that I know my tire pressure increases by 8+ lbs on a given day. It is worth a try for me, if for no other reason than as an experiment. Especially since I can see the minute-by-minute changes with the press of a button.

LEOSOPHIE

Scotty, I receive 4 Onstar monthly reports on my Silverado trucks and since switching to nitrogen the pressures have been very stable. Prior to this the reports were always different especially with weather temp changes. Costco refilled tires for no charge. The Calchrome site has an explanation of the benefits of nitrogen filling.

scottybdiving

Thanks. Exactly my point.

abcdef

This is a basic/newbie question . . . do you run the same tire pressure with the nitrogen as recommended by the manufacturer?

201mph

Racers in many forms of motorsport (not just NASCAR) use nitrogen in the tires because it performs more consistently than air. While racing radials are of much thinner construction than street tires and dissipate heat faster, the tires still gain pressure as heat builds during a run.

However, the outcome (amount of pressure build) is much more predictable and repeatable using nitrogen.

This is especially important in oval racing, because pressure affects tire circumference, and thus alters stagger (the diff btw left and right circumference), which is a major controlled variable in handling set up.

So on a street tire, nitrogen may give a more constant cold pressure than air, no matter how many heat cycles it is subjected to. Air from the gas station on a very humid day will probably have the greatest variation in cold pressure over time.

For street use, I dont see that its worth the added expense... just keep a reliable air gauge in the car and check air pressures (cold) regularly.
No worries.

lkchris

It's not nitrogen that causes this, it's the processing.

Obviously air from surroundings is inconsistent, but "bottled" gas of any variety could be made more so. Nitrogen is cheapest bottled air I suppose (not a scuba guy).