nitrogen filed tires ?
 

hi everyone, being a long time mb owner of various models including last gen. ml, I was split between the x5 and the ml320cdi.After reading a lot of inputs in this forum as well as the benz forum ,test drove both and I finally took the plunge and ordered the 3.0 in space gray with saddle brown, fully optioned except dvd and active steering (my first bmw, hopefully I will not regret it). It should be here in the 3rd week in Feb.Here is my question: the sa asked me if I wanted nitrogen in my tires(19 inch RF) for $75 claiming that it will give me a more consistant /even pressure within the tire and therefore better contact with the road . Has anyone heard anything about this or its just a waste of money on air ?:dunno:

Don't know if the evidence supports the claims. But for $75.00 Nope.
Check this out. http://www.costcoconnection.com/conn.../200410/?pg=17

I wouldn't pay anything for it, but if a shop used it I would leave it in.

Nitrogen expands at the same rate as air (which has mostly nitrogen in it anyway).

The difference is that bottled nitrogen is dry, which is good. If the air compressor has a functioning air dryer, there is no real benefit IMO. However, in the real world, unmaintained air compressors often have moisture in them, and the moisture causes problems inside the tire, whether it is corrosion or wide swings in air pressure between hot and cold. It is the moisture that expands more than the air.

Nitrogen is being touted as a wonder cure, everything from no pressure variations with temperature changes, to less leakage through the tire (the molecules are larger), to better mileage. Like all wonder cures, the claims should be evaluated carefully.

Nitrogen is the most abundant gas in the athmosphere. Costo (at least the one I go to) fills tires with nitrogen, no charge, if you buy tires there. $75 for nitrogen sounds like the dealer is hosing his customers.

+4...free, I might take it.

Nitrogen is about 78% of our "air", compressed or ambient 1 atmosphere...

The Pitch: http://www.nitrogendirect.com/N2Info.htm

I had nitrogen filled tires on my 545. The only part of the SA claim that was accurate was the consistent pressure. Nitrogen does not "leak" through a sidewall like standard inflation and maintains a more consistent pressure when heated. How this effects the average road driver, probably not much at all. And definitely not worth extra money.

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

I agree w/BigR on the no/reduced tire press change. We have it in
the fookin Fridge, (CR-V), of all cars, as they did it "free" when we got
new brakes and stuff last spring. TP has stayed spot on, even showing
less change from our Mtn house driveway reading at 5,000 to down in
the flats at closer to sea level; usually the "diff" is considerable.

NEway, cool if it's free or a reasonable 5 or 10 bucks...not 75 bucks.

Interesting!
Never heard of this before this thread but I certainly wouldn't pay for it.

I have N2 on my set of snows only. The pressure definitely stays more consistent in the winter between the widely ranging temperatures we get in Calgary. As JCL said, it's the lack of water vapor in N2 that makes the difference, not the fact that there's no C02, O2 etc. The condensing and re-vaporizing of the water makes the biggest difference in the pressure. The mix of non-condensing gas has no bearing on P vs T as they all follow Boyle's Law.

You'll definitely get some benefit from a N2 fill since you're somewhere that has real winters, but not for $75. It's free or ~$5/tire at most places that have it.

Have to agree about the pressure staying consistent with the nitrogen, it is great for fills but not worth $75.. My tyre shop filled up my 20" for $40 au and I get free top ups for the life of the tyres..