Mix nitrogen and regular air in tires?

JEDI

Lifer
Sep 25, 2001
29,391
2,738
126
i bought bf goodrich traction t/a's today from costco.

they use nitrogen (free), but fills only to manufacturer's psi. (32psi on my mazda3 16" wheels)

i usually fill to 40psi. it gives better gas milage.

so is there any downside to mixing nitrogen and regular in tires?

edit:
meant oxygen, not pure o2.

edit2:
sigh,,, regular air
 

Dman877

Platinum Member
Jan 15, 2004
2,707
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Isn't air like 70% nitrogen anyway? I don't think there would be a problem :).
 

getbush

Golden Member
Jan 19, 2001
1,771
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What are you talking about 02 for? Are you thinking of stealing your grandpas oxygen for your tires?
 

Blackjack200

Lifer
May 28, 2007
15,995
1,688
126
Air is 78% nitrogen and 21% Oxygen. Essentially, a mixture of nitrogen and O2. If there is a downside to it, millions of cars are going to have major problems.
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Originally posted by: Blackjack200
Air is 78% nitrogen and 21% Oxygen. Essentially, a mixture of nitrogen and O2. If there is a downside to it, millions of cars are going to have major problems.

all cars do eventually break
 

Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
Nitrogen in tires is a major ripoff if anyone paid for it. Do some google searching and you'll find out.

To answer your question: No, it won't hurt to top it off with air.
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Why buy high-traction tires, and then overfill them to give up the traction advantage?

But no, putting air in your tires isn't going to hurt them.
 

AMCRambler

Diamond Member
Jan 23, 2001
7,715
31
91
Yeah, overinflating your tires is putting less rubber in contact with the road. Why don't you just buy thinner tires and inflate to 32psi?
 

Vette73

Lifer
Jul 5, 2000
21,503
9
0
Originally posted by: Ktulu
I though over inflating caused tires to wear out unevenly.


It causes the middle to buldge. Since you are running on less tire then there is less restiance so milage might improve some. Look at Hybrids and see how small their tires are.

 

jaedaliu

Platinum Member
Feb 25, 2005
2,670
1
81
ride gets bumpier too. I tend to go under 3 or 4 psi when I get them checked. Smoother ride. My mileage suffers a bit, but only by 10% or so.
 

GoatMonkey

Golden Member
Feb 25, 2005
1,253
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You'll have a nice bald patch on the middle of your tires and have to replace them sooner, completely canceling out any MPG advantage you might have gotten. Plus they may have a higher chance of blowing out with increased PSI.

I had a friend who filled his car tires to 60 PSI because that's what he had always used on his bicycle.
 

SecPro

Member
Jul 17, 2007
147
0
0
Filling your tires to the max pressure listed on the sidewall will not cause your tires to wear much differently than if you inflate them to factory reccomended pressures. Rotation is the key to long tire life. Factory pressures are based on several factors, ride smoothness being one of the biggest contributors. I've always ran pressures above the factory recommended (but not above the max) and never had any problems. The rides a little harsher but the MPG is better and I think they handled better. Didn't feel mushy. YMMV.

and yes you can top those tires off with regular "air" at a gas station.
 

WolverineGator

Golden Member
Mar 20, 2001
1,011
0
76
SecPro is right. Like other posters above I thought high pressures would cause uneven wear, a harsh ride, and poor traction. I have experienced none of those things and I run my tires at 50 psi for the gas mileage improvement. The tires are wearing evenly and have about half their useful life remaining.
 

Jahee

Platinum Member
Sep 21, 2006
2,072
0
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Out of interest.. What kind of mileage increase do you get from running them at 40 rather than 32 PSI?
 

Uhtrinity

Platinum Member
Dec 21, 2003
2,263
202
106
Moisture free or dry nitrogen is used to fill cavities in high end and military grade optics. Someone probably got the idea to use low moisture nitrogen to reduce the chance corrosion to the wheels, but for it to work you would have to purge out all of the 'wet' air. Other than that it just sounds like a fad. Fyi, I run my Insights tires at 45 psi, which is within the upper psi range of the tire, some guys go as high as 50 - 60psi.
 

JulesMaximus

No Lifer
Jul 3, 2003
74,564
969
126
Originally posted by: GoatMonkey
You'll have a nice bald patch on the middle of your tires and have to replace them sooner, completely canceling out any MPG advantage you might have gotten. Plus they may have a higher chance of blowing out with increased PSI.

I had a friend who filled his car tires to 60 PSI because that's what he had always used on his bicycle.

What an idiot.

BTW-Here is some information on tire inflation.

NEVER INFLATE TO MAXIMUM TIRE PRESSURE!

There is a common misunderstanding that a tire's pressure is stamped on the sidewall. In actuality, this pressure stamped on a tire's sidewall is the MAXIMUM COLD PRESSURE that the tire will safely hold.

Many tires are rated for a maximum cold pressure of 44 psi, to allow the tires to be used on a wide variety of vehicles. Some vehicles may only require 30 psi cold pressure, others may require 38 psi cold pressure. In both cases, this cold pressure is less than the tire's MAXIMUM cold pressure, so the tire can safely be installed on these vehicles.

Tires should be inflated according to the manufacturer's cold specifications, not the maximum pressure stamped on the sidewall of the tire.

Over-inflated tires, even those inflated to maximum pressure, will cause problems with ride comfort, stability and handling, uneven wear, and potential tire failure.

Under-inflated tires will also cause these same problems, but under-inflated tires have greater potential for tire failure.

When in doubt about your tires, stop by your local reputable tire dealer and inquire at the desk. They will be happy to check your tires and tire pressure.

NEVER inflate a tire beyond its maximum rating!

NEVER drive a tire that is severely over- or under-inflated, or it may fail and blow out!

ALWAYS have your tires installed by a trained and certified tire professional.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: JulesMaximus
Originally posted by: GoatMonkey
You'll have a nice bald patch on the middle of your tires and have to replace them sooner, completely canceling out any MPG advantage you might have gotten. Plus they may have a higher chance of blowing out with increased PSI.

I had a friend who filled his car tires to 60 PSI because that's what he had always used on his bicycle.
ALWAYS have your tires installed by a trained and certified tire professional.
Uh?